Abdominal Body Composition Reference Ranges and Association With Chronic Conditions in an Age- and Sex-Stratified Representative Sample of a Geographically Defined American Population

BACKGROUND

Body composition can be accurately quantified from abdominal computed tomography (CT) exams and is a predictor for the development of aging-related conditions and for mortality. However, reference ranges for CT-derived body composition measures of obesity, sarcopenia, and bone loss have yet to be defined in the general population.

METHODS

We identified a population-representative sample of 4 900 persons aged 20 to 89 years who underwent an abdominal CT exam from 2010 to 2020. The sample was constructed using propensity score matching an age and sex stratified sample of persons residing in the 27-county region of Southern Minnesota and Western Wisconsin. The matching included race, ethnicity, education level, region of residence, and the presence of 20 chronic conditions. We used a validated deep learning based algorithm to calculate subcutaneous adipose tissue area, visceral adipose tissue area, skeletal muscle area, skeletal muscle density, vertebral bone area, and vertebral bone density from a CT abdominal section.

RESULTS

We report CT-based body composition reference ranges on 4 649 persons representative of our geographic region. Older age was associated with a decrease in skeletal muscle area and density, and an increase in visceral adiposity. All chronic conditions were associated with a statistically significant difference in at least one body composition biomarker. The presence of a chronic condition was generally associated with greater subcutaneous and visceral adiposity, and lower muscle density and vertebrae bone density.

CONCLUSIONS

We report reference ranges for CT-based body composition biomarkers in a population-representative cohort of 4 649 persons by age, sex, body mass index, and chronic conditions.

Older Tissue Age Derived From Abdominal Computed Tomography Biomarkers of Muscle, Fat, and Bone Is Associated With Chronic Conditions and Higher Mortality

OBJECTIVE

To determine whether body composition derived from medical imaging may be useful for assessing biologic age at the tissue level because people of the same chronologic age may vary with respect to their biologic age.

METHODS

We identified an age- and sex-stratified cohort of 4900 persons with an abdominal computed tomography scan from January 1, 2010, to December 31, 2020, who were 20 to 89 years old and representative of the general population in Southeast Minnesota and West Central Wisconsin. We constructed a model for estimating tissue age that included 6 body composition biomarkers calculated from abdominal computed tomography using a previously validated deep learning model.

RESULTS

Older tissue age associated with intermediate subcutaneous fat area, higher visceral fat area, lower muscle area, lower muscle density, higher bone area, and lower bone density. A tissue age older than chronologic age was associated with chronic conditions that result in reduced physical fitness (including chronic obstructive pulmonary disease, arthritis, cardiovascular disease, and behavioral disorders). Furthermore, a tissue age older than chronologic age was associated with an increased risk of death (hazard ratio, 1.56; 95% CI, 1.33 to 1.84) that was independent of demographic characteristics, county of residency, education, body mass index, and baseline chronic conditions.

CONCLUSION

Imaging-based body composition measures may be useful in understanding the biologic processes underlying accelerated aging.

Fracture Risk Among Living Kidney Donors 25 Years After Donation

Importance

Living kidney donors may have an increased risk of fractures due to reductions in kidney mass, lower concentrations of serum 1,25-dihydroxyvitamin D, and secondary increases in serum parathyroid hormone.

Objective

To compare the overall and site-specific risk of fractures among living kidney donors with strictly matched controls from the general population who would have been eligible to donate a kidney but did not do so.

Design, Setting, and Participants

This survey study was conducted between December 1, 2021, and July 31, 2023. A total of 5065 living kidney donors from 3 large transplant centers in Minnesota were invited to complete a survey about their bone health and history of fractures, and 16 156 population-based nondonor controls without a history of comorbidities that would have precluded kidney donation were identified from the Rochester Epidemiology Project and completed the same survey. A total of 2132 living kidney donors and 2014 nondonor controls responded to the survey. Statistical analyses were performed from May to August 2023.

Exposure

Living kidney donation.

Main Outcomes and Measures

The rates of overall and site-specific fractures were compared between living kidney donors and controls using standardized incidence ratios (SIRs).

Results

At the time of survey, the 2132 living kidney donors had a mean (SD) age of 67.1 (8.9) years and included 1245 women (58.4%), and the 2014 controls had a mean (SD) age of 68.6 (7.9) years and included 1140 women (56.6%). The mean (SD) time between donation or index date and survey date was 24.2 (10.4) years for donors and 27.6 (10.7) years for controls. The overall rate of fractures among living kidney donors was significantly lower than among controls (SIR, 0.89; 95% CI, 0.81-0.97). However, there were significantly more vertebral fractures among living kidney donors than among controls (SIR, 1.42; 95% CI, 1.05-1.83).

Conclusions and Relevance

This survey study found a reduced rate of overall fractures but an excess of vertebral fractures among living kidney donors compared with controls after a mean follow-up of 25 years. Treatment of excess vertebral fractures with dietary supplements such as vitamin D3 may reduce the numbers of vertebral fractures and patient morbidity.

Integrating Environmental Data with Medical Data in a Records-Linkage System to Explore Groundwater Nitrogen Levels and Child Health Outcomes

Background: The Rochester Epidemiology Project (REP) medical records-linkage system offers a unique opportunity to integrate medical and residency data with existing environmental data, to estimate individual-level exposures. Our primary aim was to provide an archetype of this integration. Our secondary aim was to explore the association between groundwater inorganic nitrogen concentration and adverse child and adolescent health outcomes. Methods: We conducted a nested case-control study in children, aged seven to eighteen, from six counties of southeastern Minnesota. Groundwater inorganic nitrogen concentration data were interpolated, to estimate exposure across our study region. Residency data were then overlaid, to estimate individual-level exposure for our entire study population (n = 29,270). Clinical classification software sets of diagnostic codes were used to determine the presence of 21 clinical conditions. Regression models were adjusted for age, sex, race, and rurality. Results: The analyses support further investigation of associations between nitrogen concentration and chronic obstructive pulmonary disease and bronchiectasis (OR: 2.38, CI: 1.64-3.46) among boys and girls, thyroid disorders (OR: 1.44, CI: 1.05-1.99) and suicide and intentional self-inflicted injury (OR: 1.37, CI: >1.00-1.87) among girls, and attention deficit conduct and disruptive behavior disorders (OR: 1.34, CI: 1.24-1.46) among boys. Conclusions: Investigators with environmental health research questions should leverage the well-enumerated population and residency data in the REP.

Convergence of four measures of multi-morbidity

Objectives

To compare the agreement between percentile ranks from 4 multi-morbidity scores.

Design

Population-based descriptive study.

Setting

Olmsted County, Minnesota (USA).

Participants

We used the medical records-linkage system of the Rochester Epidemiology Project (REP; http://www.rochesterproject.org) to identify all residents of Olmsted County, Minnesota who reached one or more birthdays between 1 January 2005 and 31 December 2014 (10 years).

Methods

For each person, we calculated 4 multi-morbidity scores using readily available diagnostic code lists from the US Department of Health and Human Services, the Clinical Classifications Software, and the Elixhauser Comorbidity Index. We calculated scores using diagnostic codes received in the 5 years before the index birthday and fit quantile regression models across age and separately by sex to transform unweighted, simple counts of conditions into percentile ranks as compared to peers of same age and of same sex. We compared the percentile ranks of the 4 multi-morbidity scores using intra-class correlation coefficients (ICCs).

Results

We assessed agreement in 181,553 persons who reached a total of 1,075,433 birthdays at ages 18 years through 85 years during the study period. In general, the percentile ranks of the 4 multi-morbidity scores exhibited high levels of agreement in 6 score-to-score pairwise comparisons. The agreement increased with older age for all pairwise comparisons, and ICCs were consistently greater than 0.65 at ages 50 years and older.

Conclusions

The assignment of percentile ranks may be a simple and intuitive way to assess the underlying trait of multi-morbidity across studies that use different measures.

Synergistic interactions of obesity with sex, education, and smoking and accumulation of multi-morbidity (MM) across the lifespan

Objectives

Obesity is a potentially modifiable risk factor that has been consistently associated with the development and progression of multi-morbidity (MM). However, obesity may be more problematic for some persons compared to others because of interactions with other risk factors. Therefore, we studied the effect of interactions between patient characteristics and overweight and obesity on the rate of accumulation of MM.

Methods

We studied 4 cohorts of persons ages 20-, 40-, 60-, and 80-years residing in Olmsted County, Minnesota between 2005 and 2014 using the Rochester Epidemiology Project (REP) medical records-linkage system. Body mass index, sex, race, ethnicity, education, and smoking status were extracted from REP indices. The rate of accumulation of MM was calculated as the number of new chronic conditions accumulated per 10 person years through 2017. Poisson rate regression models were used to identify associations between characteristics and rate of MM accumulation. Additive interactions were summarized using relative excess risk due to interaction, attributable proportion of disease, and the synergy index.

Results

Greater than additive synergistic associations were observed between female sex and obesity in the 20- and 40-year cohorts, between low education and obesity in the 20-year cohort (both sexes), and between smoking and obesity in the 40-year cohort (both sexes).

Conclusions

Interventions targeted at women, persons with lower education, and smokers who also have obesity may result in the greatest reduction in the rate of MM accumulation. However, interventions may need to focus on persons prior to mid-life to have the greatest effect.

Association of Depression and Anxiety With the Accumulation of Chronic Conditions

IMPORTANCE

Longitudinal associations between comorbid depression and anxiety with the accumulation of chronic illnesses are unclear, and questions remain about the contributions associated with each condition in the increasing prevalence of multimorbidity.

OBJECTIVE

To compare the risk and rate of accumulating chronic conditions in people with depression, anxiety, and comorbid depression and anxiety vs individuals with neither depression nor anxiety.

DESIGN, SETTING, AND PARTICIPANTS

This cohort study used the Rochester Epidemiology Project medical records-linkage system to identify residents of Olmsted County, Minnesota, from January 1, 2005, to December 31, 2014, with follow-up ending December 31, 2017. The sample was divided into cohorts anchored at birthday ages of 20, 40, and 60 years. Individuals were classified at anchoring birthday age as having depression alone, anxiety alone, comorbid depression and anxiety, or neither depression nor anxiety (reference group), using electronically extracted diagnosis codes from the International Classification of Diseases, Ninth Revision (ICD-9) in the 5 years before each anchoring birthday. Data were analyzed from August 2020 through November 2021.

EXPOSURES

Depression alone, anxiety alone, comorbid depression and anxiety, or neither depression nor anxiety (reference group).

MAIN OUTCOMES AND MEASURES

The main outcome was sex-specific risk, calculated as hazard ratios (HRs) and rates of accumulation, calculated as mean annual incidence rates per 100 person-years, of 15 common chronic conditions within each birthday age cohort through the end of study.

RESULTS

Among the 40 360 individuals included across all 3 age cohorts, 21 516 (53.3%) were women. After balancing cohorts on race, Hispanic ethnicity, education level, body mass index, smoking status, and calendar year at index birthday, the risk of accumulating chronic conditions was significantly increased among women with depression alone (cohort aged 20 years: HR, 1.20 [95% CI, 1.02-1.42]; cohort aged 40 years: HR, 1.20 [95% CI, 1.10-1.31]; cohort aged 60 years: HR, 1.09 [95% CI, 1.02-1.16]) and women with comorbid depression and anxiety (cohort aged 20 years: HR, 1.60 [95% CI, 1.28-1.99]; cohort aged 40 years: HR, 1.41 [95% CI, 1.21-1.65]; cohort aged 60 years: HR, 1.29 [95% CI, 1.15-1.44]) compared with referent women in the same birthday cohorts and in men with comorbid depression and anxiety compared with referent men in the cohort aged 20 years (HR, 1.77 [95% CI, 1.08-2.91]). For women, the rates of accumulation of conditions were significantly higher across birthday cohorts in the comorbid depression and anxiety group compared with the depression alone group (eg, cohort aged 20 years: difference, 1.2 [95% CI, 0.2-2.1] per 100 person-years) and reference group (eg, cohort aged 20 years: difference, 1.7 [95% CI, 0.9-2.6] per 100 person-years). For men, compared with the reference group, the rates of accumulation of conditions were significantly higher in men with comorbid depression and anxiety in the cohort aged 20 years (difference, 1.4 [95% CI, 0.1-2.6] per 100 person-years) and in men with depression in the cohort aged 40 years (difference, 2.0 [95% CI, 0.8-3.2] per 100 person-years).

CONCLUSIONS AND RELEVANCE

In this cohort study, the risk of accumulating chronic conditions was increased with depression and comorbid depression and anxiety in women across the age span and in younger men with comorbid depression and anxiety. Compared with women without depression or anxiety, there was a more rapid rate of accumulation of chronic conditions in women with depression and anxiety individually and an even higher rate when depression and anxiety cooccurred.

Implementing the US Department of Health and Human Services definition of multimorbidity: a comparison between billing codes and medical record review in a population-based sample of persons 4084 years old

OBJECTIVE

To assess the validity of the US Department of Health and Human Services (DHHS) definition of multimorbidity using International Classification of Diseases, ninth edition (ICD-9) codes from administrative data.

DESIGN

Cross-sectional comparison of two ICD-9 billing code algorithms to data abstracted from medical records.

SETTING

Olmsted County, Minnesota, USA.

PARTICIPANTS

An age-stratified and sex-stratified random sample of 1509 persons ages 40-84 years old residing in Olmsted County on 31 December 2010.

STUDY MEASURES

Seventeen chronic conditions identified by the US DHHS as important in studies of multimorbidity were identified through medical record review of each participant between 2006 and 2010. ICD-9 administrative billing codes corresponding to the 17 conditions were extracted using the Rochester Epidemiology Project records-linkage system. Persons were classified as having each condition using two algorithms: at least one code or at least two codes separated by more than 30 days. We compared the ICD-9 code algorithms with the diagnoses obtained through medical record review to identify persons with multimorbidity (defined as ≥2, ≥3 or ≥4 chronic conditions).

RESULTS

Use of a single code to define each of the 17 chronic conditions resulted in sensitivity and positive predictive values (PPV) ≥70%, and in specificity and negative predictive values (NPV) ≥70% for identifying multimorbidity in the overall study population. PPV and sensitivity were highest in persons 65-84 years of age, whereas NPV and specificity were highest in persons 40-64 years. The results varied by condition, and by age and sex. The use of at least two codes reduced sensitivity, but increased specificity.

CONCLUSIONS

The use of a single code to identify each of the 17 chronic conditions may be a simple and valid method to identify persons who meet the DHHS definition of multimorbidity in populations with similar demographic, socioeconomic, and health care characteristics.

Multimorbidity, ageing and mortality: normative data and cohort study in an American population

OBJECTIVES

To describe the percentile distribution of multimorbidity across age by sex, race and ethnicity, and to demonstrate the utility of multimorbidity percentiles to predict mortality.

DESIGN

Population-based descriptive study and cohort study.

SETTING

Olmsted County, Minnesota (USA).

PARTICIPANTS

We used the medical records-linkage system of the Rochester Epidemiology Project (REP; http://www.rochesterproject.org) to identify all residents of Olmsted County, Minnesota who reached one or more birthdays between 1 January 2005 and 31 December 2014 (10 years).

METHODS

For each person, we obtained the count of chronic conditions (out of 20 conditions) present on each birthday by extracting all of the diagnostic codes received in the 5 years before the index birthday from the electronic indexes of the REP. To compare each person's count to peers of same age, the counts were transformed into percentiles of the total population and displayed graphically across age by sex, race and ethnicity. In addition, quintiles 1, 2, 4 and 5 were compared with quintile 3 (reference) to predict the risk of death at 1 year, 5 years and through end of follow-up using time-to-event analyses. Follow-up was passive using the REP.

RESULTS

We identified 238 010 persons who experienced a total of 1 458 094 birthdays during the study period (median of 6 birthdays per person; IQR 3-10). The percentiles of multimorbidity across age did not vary noticeably by sex, race or ethnicity. In general, there was an increased risk of mortality at 1 and 5 years for quintiles 4 and 5 of multimorbidity. The risk of mortality for quintile 5 was greater for younger age groups and for women.

CONCLUSIONS

The assignment of multimorbidity percentiles to persons in a population may be a simple and intuitive tool to assess relative health status, and to predict short-term mortality, especially in younger persons and in women.

Pregnancy, Estrogen Exposure, and the Development of Otosclerosis: A Case-Control Study of 1196 Women

OBJECTIVE

This study sought to determine whether a history of pregnancy or bilateral oophorectomy is associated with subsequent otosclerosis development or disease severity.

STUDY DESIGN

Population-based case-control study.

SETTING

Olmsted County, Minnesota.

METHODS

Women diagnosed with otosclerosis were matched to 3 women without otosclerosis based on age and historical depth of medical records. Associations of prior delivery and bilateral oophorectomy with subsequent development of otosclerosis and with pure-tone average (PTA) at the time of otosclerosis diagnosis were evaluated.

RESULTS

We studied 1196 women: 299 cases of otosclerosis and 897 matched controls. The odds ratio for the association of ≥1 delivery with otosclerosis was 1.16 (95% confidence interval [CI] 0.85-1.60; P = .35). Odds ratios for the associations of 1, 2, 3, or ≥4 deliveries with otosclerosis were 1.22 (0.83-1.80), 1.09 (0.71-1.68), 1.28 (0.77-2.12), and 1.00 (0.54-1.84), respectively. The odds ratio for the association of prior bilateral oophorectomy with otosclerosis was 1.12 (0.58-2.18; P = .73). In cases with otosclerosis, PTA at diagnosis was not significantly higher for women with ≥1 delivery as compared with those without (median 45 dB hearing loss [HL] [interquartile range {IQR} 36-55] vs 43 [IQR 34-53]; P = 0.18) but was significantly higher for women with bilateral oophorectomy compared with those without (median 54 dB HL [IQR 44-61] vs 44 [IQR 34-53]; P = .03).

CONCLUSION

These data do not support a relationship between endogenous estrogen exposure and development of otosclerosis. Women with otosclerosis who had a history of pregnancy did not have significantly worse hearing at the time of diagnosis, suggesting that pregnancy is not associated with disease severity.

Surgery of the lateral skull base: a 50-year endeavour

Disregarding the widely used division of skull base into anterior and lateral, since the skull base should be conceived as a single anatomic structure, it was to our convenience to group all those approaches that run from the antero-lateral, pure lateral and postero-lateral side of the skull base as “Surgery of the lateral skull base”. “50 years of endeavour” points to the great effort which has been made over the last decades, when more and more difficult surgeries were performed by reducing morbidity. The principle of lateral skull base surgery, “remove skull base bone to approach the base itself and the adjacent sites of the endo-esocranium”, was then combined with function preservation and with tailoring surgery to the pathology. The concept that histology dictates the extent of resection, balancing the intrinsic morbidity of each approach was the object of the first section of the present report. The main surgical approaches were described in the second section and were conceived not as a step-by-step description of technique, but as the highlighthening of the surgical principles. The third section was centered on open issues related to the tumor and its treatment. The topic of vestibular schwannoma was investigated with the current debate on observation, hearing preservation surgery, hearing rehabilitation, radiotherapy and the recent efforts to detect biological markers able to predict tumor growth. Jugular foramen paragangliomas were treated in the frame of radical or partial surgery, radiotherapy, partial “tailored” surgery and observation. Surgery on meningioma was debated from the point of view of the neurosurgeon and of the otologist. Endolymphatic sac tumors and malignant tumors of the external auditory canal were also treated, as well as chordomas, chondrosarcomas and petrous bone cholesteatomas. Finally, the fourth section focused on free-choice topics which were assigned to aknowledged experts. The aim of this work was attempting to report the state of the art of the lateral skull base surgery after 50 years of hard work and, above all, to raise questions on those issues which still need an answer, as to allow progress in knowledge through sharing of various experiences. At the end of the reading, if more doubts remain rather than certainties, the aim of this work will probably be achieved.

Frequency and predictors of the potential overprescribing of antidepressants in elderly residents of a geographically defined U.S. population

The purpose of this study was to estimate the extent of potential antidepressant overprescribing in a geographically defined U.S. population, and to determine the indications and factors that account for it. We conducted a cohort study of new antidepressant prescriptions for elderly residents of Olmsted County, Minnesota, 2005-2012, using the Rochester Epidemiology Project medical records-linkage system. Indications for antidepressants were abstracted from health records for all cohort members. Potential antidepressant overprescribing was defined based on regulatory approval, the level of evidence identified from a standardized drug information database, and multidisciplinary expert review. Predictors of potential antidepressant overprescribing were investigated using logistic regression models, stratified by general antidepressant indication (general medical indication, specific psychiatric diagnosis, and non-specific psychiatric symptoms). Potential antidepressant overprescribing occurred in 24% of 3199 incident antidepressant prescriptions during the study period, and involved primarily newer antidepressants that were prescribed for non-specific psychiatric symptoms and subthreshold diagnoses. Potential antidepressant overprescribing was associated with nursing home residence, having a higher number of comorbid medical conditions and outpatient prescribers, taking more concomitant medications, having greater use of urgent or acute care services in the year preceding the index antidepressant prescription, and being prescribed antidepressants via telephone, e-mail, or patient portal. In conclusion, potential antidepressant overprescribing occurred in elderly persons and involved mainly newer antidepressants used for non-specific psychiatric symptoms and subthreshold diagnoses, and was associated with indicators of higher clinical complexity or severity and with prescribing without face-to-face patient contact.

CKD in Patients with Bilateral Oophorectomy

BACKGROUND AND OBJECTIVES

Premenopausal women who undergo bilateral oophorectomy are at a higher risk of morbidity and mortality. Given the potential benefits of estrogen on kidney function, we hypothesized that women who undergo bilateral oophorectomy are at higher risk of CKD.

DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS

We performed a population-based cohort study of 1653 women residing in Olmsted County, Minnesota who underwent bilateral oophorectomy before age 50 years old and before the onset of menopause from 1988 to 2007. These women were matched by age (±1 year) to 1653 referent women who did not undergo oophorectomy. Women were followed over a median of 14 years to assess the incidence of CKD. CKD was primarily defined using eGFR (eGFR<60 ml/min per 1.73 m2 on two occasions >90 days apart). Hazard ratios were derived using Cox proportional hazards models, and absolute risk increases were derived using Kaplan-Meier curves at 20 years. All analyses were adjusted for 17 chronic conditions present at index date, race, education, body mass index, smoking, age, and calendar year.

RESULTS

Women who underwent bilateral oophorectomy had a higher risk of eGFR-based CKD (211 events for oophorectomy and 131 for referent women; adjusted hazard ratio, 1.42; 95% confidence interval, 1.14 to 1.77; absolute risk increase, 6.6%). The risk was higher in women who underwent oophorectomy at age ≤45 years old (110 events for oophorectomy and 60 for referent women; adjusted hazard ratio, 1.59; 95% confidence interval, 1.15 to 2.19; absolute risk increase, 7.5%).

CONCLUSIONS

Premenopausal women who undergo bilateral oophorectomy, particularly those ≤45 years old, are at higher risk of developing CKD, even after adjusting for multiple chronic conditions and other possible confounders present at index date.

PODCAST

This article contains a podcast at https://www.asn-online.org/media/podcast/CJASN/2018_10_11_CJASNPodcast_18_1.

Loss of Ovarian Hormones and Accelerated Somatic and Mental Aging

Bilateral oophorectomy in premenopausal women is a unique condition causing the abrupt and premature loss of ovarian hormones, primarily estrogen. Bilateral oophorectomy causes an alteration of several fundamental aging processes at the cellular, tissue, organ, and system levels, leading to multimorbidity, frailty, and reduced survival. However, many questions remain unanswered.

Personal, reproductive, and familial characteristics associated with bilateral oophorectomy in premenopausal women: A population-based case-control study

OBJECTIVES

We investigated the association of personal, reproductive, and familial characteristics with bilateral oophorectomy performed for nonmalignant indications in a US population.

STUDY DESIGN

In an established cohort study, we used the records-linkage system of the Rochester Epidemiology Project (REP http://www.rochesterproject.org) to identify 1653 premenopausal women who underwent bilateral oophorectomy in Olmsted County, Minnesota between 1988 and 2007 for a nonmalignant indication. Each woman was matched by age (±1 year) to a population-based referent woman who had not undergone bilateral oophorectomy as of the index date. We used case-control analyses to investigate several characteristics associated with bilateral oophorectomy. Odds ratios and their 95% confidence intervals were adjusted for race, education, and income.

RESULTS

In the overall analyses, infertility was more common in women who underwent bilateral oophorectomy than in the controls, whereas use of oral contraceptives, a history of breast feeding, and fibrocystic breast disease were less common. The women who underwent bilateral oophorectomy weighed more than controls, had a higher body mass index and were younger at menarche. The associations were more pronounced for women who underwent the bilateral oophorectomy before age 46 years, and some associations were different for women with or without a benign ovarian indication. Reported family histories of uterine and other cancers were more common in women without a benign ovarian indication.

CONCLUSIONS

We identified a number of personal, reproductive, and familial characteristics that were associated with bilateral oophorectomy over a 20-year period. Our historical findings may help inform decision-making about oophorectomy in the future.

Rochester Epidemiology Project Data Exploration Portal

Introduction

The goal of this project was to develop an interactive, web-based tool to explore patterns of prevalence and co-occurrence of diseases using data from the expanded Rochester Epidemiology Project (E-REP) medical records-linkage system.

Methods

We designed the REP Data Exploration Portal (REP DEP) to include summary information for people who lived in a 27-county region of southern Minnesota and western Wisconsin on January 1, 2014 (n = 694,506; 61% of the entire population). We obtained diagnostic codes of the International Classification of Diseases, 9th edition, from the medical records-linkage system in 2009 through 2013 (5 years) and grouped them into 717 disease categories. For each condition or combination of 2 conditions (dyad), we calculated prevalence by dividing the number of persons with a specified condition (numerator) by the total number of persons in the population (denominator). We calculated observed-to-expected ratios (OERs) to test whether 2 conditions co-occur more frequently than would co-occur as a result of chance alone.

Results

We launched the first version of the REP DEP in May 2017. The REP DEP can be accessed at http://rochesterproject.org/portal/. Users can select 2 conditions of interest, and the REP DEP displays the overall prevalence, age-specific prevalence, and sex-specific prevalence for each condition and dyad. Also displayed are OERs overall and by age and sex and maps of county-specific prevalence of each condition and OER.

Conclusion

The REP DEP draws upon a medical records-linkage system to provide an innovative, rapid, interactive, free-of-charge method to examine the prevalence and co-occurrence of 717 diseases and conditions in a geographically defined population.

Parkinson disease with and without Dementia: A prevalence study and future projections

BACKGROUND

Limited population-based information is available on the co-occurrence of dementia and PD. However, projecting the prevalence of PD with and without dementia during the next 50 years is crucial for planning public-health and patient-care initiatives.

OBJECTIVES

The objective of this study was to project the prevalence of PD with and without dementia in the United States by 2060.

METHODS

We used the Rochester Epidemiology Project medical records-linkage system to identify all persons with PD with or without dementia residing in Olmsted County, Minnesota, on January 1, 2006. A movement disorders specialist reviewed the complete medical records of each person to confirm the presence of PD. We calculated the age- and sex-specific prevalence of PD with and without dementia and projected U.S. prevalence through 2060.

RESULTS

We identified 296 persons with PD with and without dementia on the prevalence date (187 men, 109 women); the overall prevalence increased with age from 0.01% (30-39 years) to 2.83% (≥90 years). The prevalence of PD without dementia increased with age from 0.01% (30-39 years) to 1.25% (≥90 years). The prevalence of PD with dementia increased with age from 0.10% (60-69 years) to 1.59% (≥90 years). The prevalence was higher in men than in women for all subtypes and all age groups. We project by 2060 an approximate doubling of the number of persons with PD without dementia and a tripling of the number of persons with PD with dementia in the United States.

CONCLUSIONS

The prevalence of PD with and without dementia increases with age and is higher in men than women. We project that the number of persons with PD in the United States will increase substantially by 2060. © 2018 International Parkinson and Movement Disorder Society.

Prevalence of and indications for antipsychotic use in Parkinson's disease

BACKGROUND

The prevalence of patients with PD taking antipsychotics is unknown.

OBJECTIVE

To measure the prevalence of patients with PD taking antipsychotics.

METHODS

We used the medical records-linkage system of the Rochester Epidemiology Project to study the use of antipsychotic medication in all persons with Parkinson disease in Olmsted County, Minnesota on 1 January 2006.

RESULTS

There were 296 patients with PD in Olmsted County on 1 January 2006. The overall prevalence of antipsychotic use was 9.8% (29 of 296); 95.5% (28 of 29) of the patients had dementia when initiating antipsychotics. The most frequent indication (71.4%; 20 of 28) was psychosis or behavior threatening to the patient or others.

CONCLUSIONS

The prevalence of antipsychotic use in patients with PD is lower than expected from previously reported cumulative incidences. Dementia is highly prevalent in those starting antipsychotics. Most of the patients on antipsychotics had a reasonable risk-benefit ratio for taking them. © 2017 International Parkinson and Movement Disorder Society.

Cohort profile: the Mayo Clinic Cohort Study of Oophorectomy and Aging-2 (MOA-2) in Olmsted County, Minnesota (USA)

PURPOSE

This cohort study was established to investigate the effects of unilateral and bilateral oophorectomy on the ageing processes in women.

PARTICIPANTS

We used the records-linkage system of the Rochester Epidemiology Project (REP, http://www.rochesterproject.org) to identify 570 women who underwent unilateral oophorectomy and 1653 women who underwent bilateral oophorectomy in Olmsted County, Minnesota from 1988 through 2007 (20 years). Each woman was matched by age (±1 year) to a population-based referent woman who had not undergone any oophorectomy (570 referent women) or bilateral oophorectomy (1653 referent women). These four cohorts are being followed to assess morbidity and mortality and to study imaging and biological markers related to ageing.

FINDINGS TO DATE

An extensive medical record abstraction using the REP has been completed for each woman to obtain demographic, reproductive and adult life characteristics and extensive clinical information about the surgical procedure and subsequent oestrogen replacement therapy (or other sex steroid therapy). The cohorts have been used to date to study the accumulation of multiple chronic conditions following bilateral oophorectomy in women with or without chronic conditions at the time of the oophorectomy (or index date). From the cohorts, we have also derived a sample of 128 pairs of women for a case-control study linking adverse childhood or adult experiences to the risk of bilateral oophorectomy.

FUTURE PLANS

We hypothesise that the abrupt hormonal changes caused by bilateral oophorectomy in younger women have a major effect on the ageing processes across the full body. Therefore, we plan to investigate the risk of a wide range of chronic conditions following bilateral oophorectomy. Specific studies are underway for kidney diseases, psychiatric diseases and neurological diseases. In addition, we plan to invite a subsample of women from the bilateral oophorectomy cohort to participate in an in-person study involving brain imaging and the collection of biomarkers.

Bilateral Oophorectomy and Accelerated Aging: Cause or Effect?

Background

The cause-effect relationship between bilateral oophorectomy and accelerated aging remains controversial. We conducted new analyses to further address this controversy.

Methods

The Rochester Epidemiology Project records-linkage system was used to identify all premenopausal women who underwent bilateral oophorectomy for a noncancerous condition before age 50 years between 1988 and 2007 in Olmsted County, MN. Each woman was randomly matched to a referent woman born in the same year (±1 year) who had not undergone bilateral oophorectomy. We studied the rate of accumulation of 18 common chronic conditions over a median of approximately 14 years of follow-up (historical cohort study). Analyses were restricted to women free of any of the 18 chronic conditions at the time of oophorectomy (or index date).

Results

After adjustments for race/ethnicity, education, body mass index, smoking, and age and calendar year at the index date, women who underwent oophorectomy before age 46 years experienced an accelerated rate of accumulation of the 18 chronic conditions considered together (hazard ratio = 1.24; 95% confidence interval: 1.12, 1.37; p < .001). The single-year incidence rate of new conditions was most different in the first 6 years after oophorectomy but the difference attenuated thereafter. Findings did not vary by surgical indication for the oophorectomy.

Conclusions

Bilateral oophorectomy is associated with a higher risk of multimorbidity among women who did not have any of the 18 selected conditions at baseline. The association did not vary by surgical indication for oophorectomy. Our findings suggest that bilateral oophorectomy is causally linked to accelerated aging.

Survival and Causes of Death Among People With Clinically Diagnosed Synucleinopathies With Parkinsonism: A Population-Based Study

Importance

To our knowledge, a comprehensive study of the survival and causes of death of persons with synucleinopathies compared with the general population has not been conducted. Understanding the long-term outcomes of these conditions may inform patients and caregivers of the expected disease duration and may help with care planning.

Objective

To compare survival rates and causes of death among patients with incident, clinically diagnosed synucleinopathies and age- and sex-matched referent participants.

Design, Setting, and Participants

This population-based study used the Rochester Epidemiology Project medical records-linkage system to identify all residents in Olmsted County, Minnesota, who received a diagnostic code of parkinsonism from 1991 through 2010. A movement-disorders specialist reviewed the medical records of each individual to confirm the presence of parkinsonism and determine the type of synucleinopathy. For each confirmed patient, an age- and sex-matched Olmsted County resident without parkinsonism was also identified.

Main Outcomes and Measures

We determined the age- and sex-adjusted risk of death for each type of synucleinopathy, the median time from diagnosis to death, and the causes of death.

Results

Of the 461 patients with synucleinopathies, 279 (60.5%) were men, and of the 452 referent participants, 272 (60.2%) were men. From 1991 through 2010, 461 individuals received a diagnosis of a synucleinopathy (309 [67%] of Parkinson disease, 81 [17.6%] of dementia with Lewy bodies, 55 [11.9%] of Parkinson disease dementia, and 16 [3.5%] of multiple system atrophy with parkinsonism). During follow-up, 68.6% (n = 316) of the patients with synucleinopathies and 48.7% (n = 220) of the referent participants died. Patients with any synucleinopathy died a median of 2 years earlier than referent participants. Patients with multiple system atrophy with parkinsonism (hazard ratio, 10.51; 95% CI, 2.92-37.82) had the highest risk of death compared with referent participants, followed by those with dementia with Lewy bodies (hazard ratio, 3.94; 95% CI, 2.61-5.94), Parkinson disease with dementia (hazard ratio, 3.86; 95% CI, 2.36-6.30), and Parkinson disease (hazard ratio, 1.75; 95% CI, 1.39-2.21). Neurodegenerative disease was the most frequent cause of death listed on the death certificate for patients, and cardiovascular disease was the most frequent cause of death among referent participants.

Conclusions and Relevance

Individuals with multiple system atrophy with parkinsonism, dementia with Lewy bodies, and Parkinson disease dementia have increased mortality compared with the general population. The mortality among persons with Parkinson disease is only moderately increased compared with the general population.

Adverse childhood or adult experiences and risk of bilateral oophorectomy: a population-based case-control study

OBJECTIVES

Bilateral oophorectomy has commonly been performed in conjunction with hysterectomy even in women without a clear ovarian indication; however, oophorectomy may have long-term deleterious consequences. To better understand this surgical practice from the woman's perspective, we studied the possible association of adverse childhood or adult experiences with the subsequent occurrence of bilateral oophorectomy.

DESIGN

Population-based case-control study.

SETTING

Olmsted County, Minnesota (USA).

PARTICIPANTS

From an established population-based cohort study, we sampled 128 women who underwent bilateral oophorectomy before age 46 years for a non-cancerous condition in 1988-2007 (cases) and 128 age-matched controls (±1 year).

METHODS

Information about adverse experiences was abstracted from the medical records dating back to age 15 years or earlier archived in the Rochester Epidemiology Project (REP) records-linkage system. Adverse childhood experiences were summarised using the Adverse Childhood Experience (ACE) score.

RESULTS

We observed an association of bilateral oophorectomy performed before age 46 years with verbal or emotional abuse, physical abuse, any abuse, substance abuse in the household, and with an ACE score ≥1 experienced before age 19 years (OR=3.23; 95% CI 1.73 to 6.02; p<0.001). In women who underwent the oophorectomy before age 40 years, we also observed a strong association with physical abuse experienced during adulthood (OR=4.33; 95% CI 1.23 to 15.21; p=0.02). Several of the associations were higher in women who underwent oophorectomy at a younger age (<40 years) and in women without an ovarian indication for the surgery. None of the psychosocial or medical variables explored as potential confounders or intervening variables changed the results noticeably.

CONCLUSIONS

Women who suffered adverse childhood experiences or adult abuse are at increased risk of undergoing bilateral oophorectomy before menopause. We suggest that the association may be explained by a series of biological, emotional, and psychodynamic mechanisms.

Time Trends in the Incidence of Parkinson Disease

IMPORTANCE

Changes over time in the incidence of parkinsonism and Parkinson disease (PD) remain uncertain.

OBJECTIVE

To investigate secular trends (period effects) and birth cohort trends in the incidence of parkinsonism and PD over 30 years in a geographically defined American population.

DESIGN, SETTING, AND PARTICIPANTS

We used the medical records-linkage system of the Rochester Epidemiology Project to identify incidence cases of PD and other types of parkinsonism in Olmsted County, Minnesota, from 1976 to 2005. All cases were classified by a movement disorder specialist using defined criteria through the review of the complete medical records within the system. The analyses for this study were conducted between May 2015 and January 2016.

MAIN OUTCOMES AND MEASURES

Incidence rates of parkinsonism and PD over 30 years. We tested for secular trends (period effects) using negative binomial regression models and for birth cohort effects using age-period-cohort models.

RESULTS

Of 906 patients with parkinsonism, 501 were men, and the median age at onset was 74 years (interquartile range, 66-81 years). Of the 464 patients with PD, 275 were men, and the median age at onset was 73 years (interquartile range, 64-80 years). The overall incidence rates increased significantly over 30 years in men for both parkinsonism (relative risk [RR], 1.17 per decade; 95% CI, 1.03-1.33) and PD (RR, 1.24 per decade; 95% CI, 1.08-1.43). These trends were driven primarily by the older age groups. In particular, for men 70 years or older, incidence rates increased for both parkinsonism (RR, 1.24 per decade; 95% CI, 1.07-1.44) and PD (RR, 1.35 per decade; 95% CI, 1.10-1.65). The secular trends were not significant for women overall or in age strata. We observed an increased risk for both men and women born in the 1920 cohort (1915-1924). However, this birth cohort effect was significant only for PD and only in men.

CONCLUSIONS AND REVELANCE

Our study suggests that the incidence of parkinsonism and PD may have increased between 1976 and 2005, particularly in men 70 years and older. These trends may be associated with the dramatic changes in smoking behavior that took place in the second half of the 20th century or with other lifestyle or environmental changes. However, the trends could be spurious and need to be confirmed in other populations.

Linking medical and dental health record data: a partnership with the Rochester Epidemiology Project

PURPOSE

The purpose of this project was to expand the Rochester Epidemiology Project (REP) medical records linkage infrastructure to include data from oral healthcare providers. The goal of this linkage is to facilitate research studies examining the role of oral health in overall health and quality of life.

PARTICIPANTS

Eight dental practices joined the REP between 2011 and 2015. The REP study team has linked oral healthcare information with medical record information from local healthcare providers for 31 750 participants who have resided in Olmsted County, Minnesota. Overall, 17 718 (56%) participants are women, 14 318 (45%) are 40 years of age or older and 26 090 (82%) are white.

FINDINGS TO DATE

A first study using this new information was recently completed. This resource was used to determine whether the 2007 guidelines from the American Heart Association affected prescription rates of antibiotics to patients with moderate-risk cardiac conditions prior to dental procedures. The REP infrastructure was used to identify a series of patients diagnosed with moderate-risk cardiac conditions by the local healthcare providers (n=1351), and to abstract antibiotic prescriptions from dental records both pre-2007 and post-2007. Antibiotic prescriptions prior to dental procedures declined from 62% to 7% following the change in guidelines.

FUTURE PLANS

Dental data from participating practitioners will be updated on an annual basis, and new dental data will be linked to patient medical records. In addition, we will continue to invite new dental practices to participate in the REP. Finally, we will continue to use this research infrastructure to investigate associations between oral and medical health, and will present findings at conferences and in the scientific literature.

Clinical Trials Targeting Aging and Age-Related Multimorbidity

Background

There is growing interest in identifying interventions that may increase health span by targeting biological processes underlying aging. The design of efficient and rigorous clinical trials to assess these interventions requires careful consideration of eligibility criteria, outcomes, sample size, and monitoring plans.

Methods

Experienced geriatrics researchers and clinical trialists collaborated to provide advice on clinical trial design.

Results

Outcomes based on the accumulation and incidence of age-related chronic diseases are attractive for clinical trials targeting aging. Accumulation and incidence rates of multimorbidity outcomes were developed by selecting at-risk subsets of individuals from three large cohort studies of older individuals. These provide representative benchmark data for decisions on eligibility, duration, and assessment protocols. Monitoring rules should be sensitive to targeting aging-related, rather than disease-specific, outcomes.

Conclusions

Clinical trials targeting aging are feasible, but require careful design consideration and monitoring rules.

Accelerated Accumulation of Multimorbidity After Bilateral Oophorectomy: A Population-Based Cohort Study

OBJECTIVE

To study the association between bilateral oophorectomy and the rate of accumulation of multimorbidity.

PATIENTS AND METHODS

In this historical cohort study, the Rochester Epidemiology Project records-linkage system was used to identify all premenopausal women who underwent bilateral oophorectomy before age 50 years between January 1, 1988, and December 31, 2007, in Olmsted County, Minnesota. Each woman was randomly matched to a referent woman born in the same year (±1 year) who had not undergone bilateral oophorectomy. We studied the rate of accumulation of 18 common chronic conditions over a median of approximately 14 years of follow-up.

RESULTS

Although women who underwent bilateral oophorectomy already had a higher multimorbidity burden at the time of oophorectomy, they also experienced an increased risk of subsequent multimorbidity. After adjustments for 18 chronic conditions present at baseline, race/ethnicity, education, body mass index, smoking, age at baseline, and calendar year at baseline, women who underwent oophorectomy before age 46 years experienced an increased risk of depression, hyperlipidemia, cardiac arrhythmias, coronary artery disease, arthritis, asthma, chronic obstructive pulmonary disease, and osteoporosis. In addition, they experienced an accelerated rate of accumulation of the 18 chronic conditions considered together (hazard ratio, 1.22; 95% CI, 1.14-1.31; P<.001). Several of these associations were reduced in women who received estrogen therapy.

CONCLUSION

Bilateral oophorectomy is associated with a higher risk of multimorbidity, even after adjustment for conditions present at baseline and for several possible confounders. However, several of these associations were reduced in women who received estrogen therapy.

Incidence and time trends of drug-induced parkinsonism: A 30-year population-based study

Background

Epidemiological studies of drug‐induced parkinsonism remain limited.

Objectives

To investigate the incidence and time trends of drug‐induced parkinsonism over 30 years in a geographically defined American population.

Methods

We used the medical records‐linkage system of the Rochester Epidemiology Project to identify all persons in Olmsted County, Minnesota, who received a screening diagnostic code for parkinsonism from 1976 through 2005. A movement disorders specialist reviewed the complete medical records of each person to confirm the presence of drug‐induced parkinsonism associated with dopamine‐blocking or dopamine‐depleting medications.

Results

Among 906 incident cases of parkinsonism from 1976 to 2005, 108 persons had drug‐induced parkinsonism (11.9%). The average annual incidence rate of drug‐induced parkinsonism was 3.3 per 100,000 person‐years, was higher in women, and increased with older age. Drug‐induced parkinsonism was the fifth‐most common type of parkinsonism overall; however, it was the most common type among persons younger than age 40 years. Typical antipsychotic drugs were the most common class of drugs associated with parkinsonism, whereas atypical antipsychotic drugs were rarely involved. The incidence rate of drug‐induced parkinsonism decreased 32.0% per decade (relative risk = 0.68; 95% confidence interval: 0.49–0.94) and 68.6% over the 30 years of the study. The decrease was similar in men (65.2%) and women (69.4%); however, the trend was significant only in women.

Conclusions

The incidence of drug‐induced parkinsonism increased with older age and was higher in women at all ages. Typical antipsychotic drugs were the most common cause. The incidence of drug‐induced parkinsonism decreased over the 30 years of the study because of changes in drug use. © 2016 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Frailty Trajectories in an Elderly Population-Based Cohort

OBJECTIVES

To identify distinct frailty trajectories (clusters of individuals following a similar progression of frailty over time) in an aging population and to estimate associations between frailty trajectories and emergency department visits, hospitalizations, and all-cause mortality.

DESIGN

Population-based cohort study.

SETTING

Olmsted County, Minnesota.

PARTICIPANTS

Olmsted County, Minnesota residents aged 60-89 in 2005.

MEASUREMENTS

Longitudinal changes in frailty between 2005 and 2012 were measured by constructing a yearly Rockwood frailty index incorporating body mass index, 17 comorbidities, and 14 activities of daily living. The frailty index measures variation in health status as the proportion of deficits present of the 32 considered (range 0-1).

RESULTS

Of the 16,443 Olmsted County residents aged 60-89 in 2005, 12,270 (74.6%) had at least 3 years of frailty index measures and were retained for analysis. The median baseline frailty index increased with age (0.11 for 60-69, 0.14 for 70-79, 0.19 for 80-89). Three distinct frailty trajectories were identified in individuals aged 60-69 at baseline and two trajectories in those aged 70-79 and 80-89. Within each decade of age, increasing frailty trajectories were associated with greater risks of emergency department visits, hospitalization, and all-cause mortality, even after adjustment for baseline frailty index.

CONCLUSION

The number of frailty trajectories differed according to age. Within each age group, those in the highest frailty trajectory had greater healthcare use and worse survival. Frailty trajectories may offer a way to target aging individuals at high risk of hospitalization or death for therapeutic or preventive interventions.

Prevalence of Combined Somatic and Mental Health Multimorbidity: Patterns by Age, Sex, and Race/Ethnicity

BACKGROUND

The coexistence of chronic mental health conditions with somatic conditions (somatic-mental multimorbidity, or SMM) is common and has been associated with greater symptom burden and functional impairment, higher costs, and excess mortality. However, most existing literature focused on the co-occurrence of an index mental health condition with specific additional conditions. By contrast, we studied the prevalence and patterns of SMM more broadly considering 19 selected conditions, and we focused on differences by age, sex, and race/ethnicity.

METHODS

The Rochester Epidemiology Project (REP) records-linkage system was used to identify all residents of Olmsted County, MN, on April 1, 2010. We identified individuals with each of 19 common chronic conditions, including 5 mental health conditions, using the International Classification of Diseases, ninth revision (ICD-9) codes received from any health care provider between April 1, 2005 and March 31, 2010.

RESULTS

Among the 138,858 residents of the county, 52.4% were women, and 7.9% had SMM. SMM increased steeply with older age, was 1.7 times more common in women, and was lower in Asians compared with whites. Of the 10,903 persons with SMM, 7,739 (71.0%) were younger than 65 years. Depressive and anxiety disorders were the most common conditions involved in SMM. The dyads that were observed more frequently or less frequently than expected by chance varied in composition by age and sex.

CONCLUSIONS

SMM that reaches medical attention is highly prevalent across all age groups, is more frequent in women, is less frequent in Asians, and encompasses a wide range of conditions.

Vestibular schwannoma and pituitary adenoma in the same patient: coincidence or novel clinical association?

Over the years the authors have evaluated a number of patients with vestibular schwannomas (VS) who have also been diagnosed with a pituitary adenoma (PA). No associations between these tumors have been established to date. The objective of the current study is to investigate the epidemiological association between VS and PA via a population-based study and to supplement these data with a retrospective case series of 12 patients who were evaluated at the authors' center over the past 15 years. An analysis of the Surveillance, Epidemiology, and End Results database including all patients identified with a diagnosis of VS and/or PA was performed. A comparison between the observed and expected annual incidence was calculated and population differences between those with VS + PA were compared with single tumor populations. 9888 patients with VS and 26,577 patients with PA were identified among 822.9 million person-years. Within these populations, 31 patients were diagnosed with both tumor types. Overall, 1 in every 319 patients with VS was also diagnosed with a PA. The average annual incidence for VS was 1.2 per 100,000 persons per year while the average PA rate was 3.2 per 100,000 persons per year. The observed rate of co-incident VS and PA was greater than what is expected by chance alone assuming independence. The cohort of patients with coexisting VS and PA were older and more commonly male compared to VS-only or PA-only groups. These data strongly suggest that a common environmental or genetic predisposition exists for VS and PA development. Further study of this population may help elucidate the cause of tumorigenesis in a subset of patients with seemingly sporadic tumors.

Risk of developing multimorbidity across all ages in an historical cohort study: differences by sex and ethnicity

OBJECTIVE

To study the incidence of de novo multimorbidity across all ages in a geographically defined population with an emphasis on sex and ethnic differences.

DESIGN

Historical cohort study.

SETTING

All persons residing in Olmsted County, Minnesota, USA on 1 January 2000 who had granted permission for their records to be used for research (n=123 716).

PARTICIPANTS

We used the Rochester Epidemiology Project medical records-linkage system to identify all of the county residents. We identified and removed from the cohort all persons who had developed multimorbidity before 1 January 2000 (baseline date), and we followed the cohort over 14 years (1 January 2000 through 31 December 2013).

MAIN OUTCOME MEASURES

Incident multimorbidity was defined as the development of the second of 2 conditions (dyads) from among the 20 chronic conditions selected by the US Department of Health and Human Services. We also studied the incidence of the third of 3 conditions (triads) from among the 20 chronic conditions.

RESULTS

The incidence of multimorbidity increased steeply with older age; however, the number of people with incident multimorbidity was substantially greater in people younger than 65 years compared to people age 65 years or older (28 378 vs 6214). The overall risk was similar in men and women; however, the combinations of conditions (dyads and triads) differed extensively by age and by sex. Compared to Whites, the incidence of multimorbidity was higher in Blacks and lower in Asians.

CONCLUSIONS

The risk of developing de novo multimorbidity increases steeply with older age, varies by ethnicity and is similar in men and women overall. However, as expected, the combinations of conditions vary extensively by age and sex. These data represent an important first step toward identifying the causes and the consequences of multimorbidity.

Relationship between body mass index and the incidence of inguinal hernia repairs: a population-based study in Olmsted County, MN

PURPOSE

The relationship between body mass index (BMI) and the risk of inguinal hernia development is unclear. To explore the relationship, we determined whether the incidence of inguinal hernia repairs (IHR) varied across patients with different BMI categories.

STUDY DESIGN

A population-based incidence study was undertaken. We reviewed all IHR performed on adult residents of Olmsted County, MN from 2004 to 2008. Cases were ascertained through the Rochester Epidemiology Project, a records-linkage system with more than 97% population coverage.

RESULTS

During the study period, a total of 1,168 IHR were performed on 879 men and 107 women. The median BMI of the cohort was 26.7 kg/m2 (range 14.9-58.1, interquartile range 23.9-28.9). Incidence rates varied significantly as a function of BMI (p<0.001). Rates were highest among men who were either normal weight or overweight (419.8 and 421.1 per 100,000 person-years for BMI<25 and BMI 25-29.9, respectively), and lowest for obese and morbidly obese men (273.5 and 99.4 per 100,000 person-years for BMI 30-34.9 and BMI C 35, respectively). Findings were similar across all age categories and in patients who had an IHR that was initial or recurrent, direct or indirect, and unilateral or bilateral.

CONCLUSIONS

The incidence of IHR decreased as BMI increased. Obese and morbidly obese patients had a lower incidence of IHR than those who were normal weight or overweight. The causal mechanisms leading to such a relationship are unclear and warrant further study.

Prevalence of multimorbidity in a geographically defined American population: patterns by age, sex, and race/ethnicity

OBJECTIVE

To describe the prevalence of multimorbidity involving 20 selected chronic conditions in a geographically defined US population, emphasizing age, sex, and racial/ethnic differences.

PATIENTS AND METHODS

Using the Rochester Epidemiology Project records linkage system, we identified all residents of Olmsted County, Minnesota, on April 1, 2010, and electronically extracted the International Classification of Diseases, Ninth Revision codes associated with all health care visits made between April 1, 2005, and March 31, 2010 (5-year capture frame). Using these codes, we defined the 20 common chronic conditions recommended by the US Department of Health and Human Services. We counted only persons who received at least 2 codes for a given condition separated by more than 30 days, and we calculated the age-, sex-, and race/ethnicity-specific prevalence of multimorbidity.

RESULTS

Of the 138,858 study participants, 52.4% were women (n=72,732) and 38.9% had 1 or more conditions (n=54,012), 22.6% had 2 or more conditions (n=31,444), and 4.9% had 5 or more conditions (n=6853). The prevalence of multimorbidity (≥2 conditions) increased steeply with older age and reached 77.3% at 65 years and older. However, the absolute number of people affected by multimorbidity was higher in those younger than 65 years. Although the prevalence of multimorbidity was similar in men and women overall, the most common dyads and triads of conditions varied by sex. Compared with white persons, the prevalence of multimorbidity was slightly higher in black persons and slightly lower in Asian persons.

CONCLUSION

Multimorbidity is common in the general population; it increases steeply with older age, has different patterns in men and women, and varies by race/ethnicity.

Oophorectomy, estrogen, and dementia: a 2014 update

Current evidence suggests that estrogen may have beneficial, neutral, or detrimental effects on the brain depending on age, type of menopause (natural versus induced), or stage of menopause (early versus late), consistent with the timing hypothesis. Three studies have now compared women who underwent bilateral oophorectomy before menopause with referent women and consistently showed an increased risk of cognitive decline and dementia. These studies suggest a sizeable neuroprotective effect of estrogen naturally produced by the ovaries before age 50 years. In this article, we focus on neuroprotection as related to cognitive decline and dementia. Several case-control studies and cohort studies also showed neuroprotective effects in women who received estrogen treatment (ET) in the early postmenopausal stage (most commonly at ages 50-60 years). The majority of women in those observational studies had undergone natural menopause and were treated for the relief of menopausal symptoms. However, the clinical trials by the Women's Health Initiative showed that women who initiated ET alone or in combination with a progestin in the late postmenopausal stage (ages 65-79 years) experienced an increased risk of dementia and cognitive decline regardless of the type of menopause. Three observational studies have now formally tested the timing hypothesis, and showed that the neuroprotective or harmful effects of estrogen depend on age at the time of initiation of treatment and on stage of menopause. Therefore, women who undergo bilateral oophorectomy before the onset of menopause or women who experience premature or early natural menopause should be considered for hormonal treatment until the average age of natural menopause (around age 50 years). Recommendations for the use of ET by women who experience natural menopause at typical ages remain less certain, and more research is needed.

Incidence of dementia with Lewy bodies and Parkinson disease dementia

IMPORTANCE

Epidemiologic data on dementia with Lewy bodies (DLB) and Parkinson disease dementia (PDD) remain limited in the United States and worldwide. These data are essential to guide research and clinical or public health interventions.

OBJECTIVE

To investigate the incidence of DLB among residents of Olmsted County, Minnesota, and compare it with the incidence of PDD.

DESIGN

The medical records linkage system of the Rochester Epidemiology Project was used to identify all persons who developed parkinsonism and, in particular, DLB or PDD from 1991 through 2005 (15 years). A movement disorders specialist reviewed the complete medical records of each suspected patient to confirm the diagnosis.

SETTING

Olmsted County, Minnesota, from 1991 through 2005 (15 years).

PARTICIPANTS

All the residents of Olmsted County, Minnesota, who gave authorization for medical record research.

MAIN OUTCOMES AND MEASURES

Incidence of DLB and PDD.

RESULTS

Among 542 incident cases of parkinsonism, 64 had DLB and 46 had PDD. The incidence rate of DLB was 3.5 per 100,000 person-years overall, and it increased steeply with age. The incidence of PDD was 2.5 overall and also increased steeply with age. The incidence rate of DLB and PDD combined was 5.9. Patients with DLB were younger at onset of symptoms than patients with PDD and had more hallucinations and cognitive fluctuations. Men had a higher incidence of DLB than women across the age spectrum. The pathology was consistent with the clinical diagnosis in 24 of 31 patients (77.4%) who underwent autopsy.

CONCLUSIONS AND RELEVANCE

The overall incidence rate of DLB is lower than the rate of Parkinson disease. The incidence of DLB increases steeply with age and is markedly higher in men. This men to women difference may suggest different etiologic mechanisms. Our findings may guide health care planning and prompt new studies.

Incidence and pathology of synucleinopathies and tauopathies related to parkinsonism

IMPORTANCE

The frequency and distribution of synucleinopathies and tauopathies manifesting with parkinsonism in the general population are poorly understood, thus affecting health care planning and research.

OBJECTIVE

To investigate the incidence and distribution of specific types of parkinsonism and related proteinopathies.

DESIGN

We used the medical records-linkage system of the Rochester Epidemiology Project to identify all subjects who received a screening diagnostic code related to parkinsonism in Olmsted County, Minnesota, from January 1, 1991, through December 31, 2005 (15 years). A movement disorders specialist reviewed the complete medical records of each subject who screened positive to determine the type of parkinsonism and the presumed proteinopathy using specified criteria.

SETTING

Geographically defined population.

PARTICIPANTS

All residents of Olmsted County who provided authorization to use their data for medical records research (population-based sample).

MAIN OUTCOME AND MEASURES

Incidence of parkinsonism and specific proteinopathies.

RESULTS

Among 542 incident cases of parkinsonism, 409 (75.5%) were classified as proteinopathies. Of the 389 patients with presumed synucleinopathies (71.8%), 264 had Parkinson disease (48.7% of all cases). The incidence rate of synucleinopathies was 21.0 per 100 000 person-years overall and increased steeply with age. The incidence rate of tauopathies was 1.1 overall (20 cases), and the most common tauopathy was progressive supranuclear palsy (16 cases). Thirty-six subjects had drug-induced parkinsonism (6.6%), 11 had vascular parkinsonism (2.0%), 1 had amyotrophic lateral sclerosis in parkinsonism (0.2%), 1 had parkinsonism secondary to surgery (0.2%), and 84 remained unspecified (15.5%). Men had a higher incidence than women for most types of parkinsonism. Findings at brain autopsy confirmed the clinical diagnosis in 53 of 65 patients who underwent autopsy (81.5%).

CONCLUSIONS AND RELEVANCE

The incidence of proteinopathies related to parkinsonism increases steeply with age and is consistently higher in men than women. Clinically diagnosed synucleinopathies are much more common than tauopathies. Findings at autopsy confirm the clinical diagnosis of presumed proteinopathy. Our findings may guide health care planning and prompt new research directions.

Completion of the human papillomavirus vaccination series lags in Somali adolescents

OBJECTIVE

It is unknown whether the Somali population in the United States is likely to participate in human papillomavirus (HPV) vaccination. We aimed to determine whether Somali girls living in a US community are following the recommendations for HPV vaccination.

MATERIALS AND METHODS

We conducted a study of HPV vaccination among Somali girls seen at Mayo Clinic, Rochester, MN. Each Somali subject was matched by year of birth to white/non-Hispanic subjects in a 1:3 ratio. We abstracted information between August 1, 2006, and December 31, 2009, related to HPV vaccine series initiation and completion. Initiation and completion frequencies were compared between study groups using the χ(2) test.

RESULTS

A total of 251 Somali and 727 white/non-Hispanic girls were identified, using the Rochester Epidemiology Project, who met all inclusion criteria for final analysis. A total of 114 Somali girls (45%) and 334 white/non-Hispanic girls (46%) initiated the series (odds ratio = 0.98; 95% confidence interval = 0.73-1.31), but only 59 Somali girls (52%) completed the vaccination series, compared with 240 (72%) of the white/non-Hispanic girls (odds ratio = 0.42; 95% confidence interval = 0.27-0.65).

CONCLUSIONS

We found Somali girls to be generally accepting of initiating the HPV vaccine series but less likely to complete the series as compared with white non-Hispanic girls of the same age.

Risk factors for Parkinson's disease may differ in men and women: an exploratory study

Although several environmental and genetic risk or protective factors have been associated with Parkinson's disease (PD), their interactions overall and in men and women separately remain unknown. We used the medical records-linkage system of the Rochester Epidemiology Project to identify 196 subjects who developed PD in Olmsted County, MN, from 1976 through 1995. Each incident case was matched by age (±1 year) and sex to a general population control. We considered the following 12 risk or protective factors: personal history of head trauma, pesticide use, immunologic diseases, anemia, hysterectomy (in women only), cigarette smoking, coffee consumption, and education; and family history of parkinsonism, essential tremor, dementia, or psychiatric disorders. We used recursive partitioning analyses to explore interactions overall and in men and women separately and used logistic regression analyses to test for interactions. In the overall group, we observed the independent effects of anemia, lack of coffee consumption (never vs. ever), and head trauma; however, the findings were different in men and women. In men, we observed the independent effects of lack of coffee consumption (never vs. ever), head trauma, and pesticide use, and a suggestive synergistic interaction between immunologic diseases and family history of dementia. By contrast, in women, anemia was the most important factor and we observed a suggestive synergistic interaction between anemia and higher education. Risk factors for PD and their interactions may differ in men and women.

History of the Rochester Epidemiology Project: half a century of medical records linkage in a US population

The Rochester Epidemiology Project (REP) has maintained a comprehensive medical records linkage system for nearly half a century for almost all persons residing in Olmsted County, Minnesota. Herein, we provide a brief history of the REP before and after 1966, the year in which the REP was officially established. The key protagonists before 1966 were Henry Plummer, Mabel Root, and Joseph Berkson, who developed a medical records linkage system at Mayo Clinic. In 1966, Leonard Kurland established collaborative agreements with other local health care providers (hospitals, physician groups, and clinics [primarily Olmsted Medical Center]) to develop a medical records linkage system that covered the entire population of Olmsted County, and he obtained funding from the National Institutes of Health to support the new system. In 1997, L. Joseph Melton III addressed emerging concerns about the confidentiality of medical record information by introducing a broad patient research authorization as per Minnesota state law. We describe how the key protagonists of the REP have responded to challenges posed by evolving medical knowledge, information technology, and public expectation and policy. In addition, we provide a general description of the system; discuss issues of data quality, reliability, and validity; describe the research team structure; provide information about funding; and compare the REP with other medical information systems. The REP can serve as a model for the development of similar research infrastructures in the United States and worldwide.

Data resource profile: the Rochester Epidemiology Project (REP) medical records-linkage system

The Rochester Epidemiology Project (REP) medical records-linkage system was established in 1966 to capture health care information for the entire population of Olmsted County, MN, USA. The REP includes a dynamic cohort of 502 820 unique individuals who resided in Olmsted County at some point between 1966 and 2010, and received health care for any reason at a health care provider within the system. The data available electronically (electronic REP indexes) include demographic characteristics, medical diagnostic codes, surgical procedure codes and death information (including causes of death). In addition, for each resident, the system keeps a complete list of all paper records, electronic records and scanned documents that are available in full text for in-depth review and abstraction. The REP serves as the research infrastructure for studies of virtually all diseases that come to medical attention, and has supported over 2000 peer-reviewed publications since 1966. The system covers residents of all ages and both sexes, regardless of socio-economic status, ethnicity or insurance status. For further information regarding the use of the REP for a specific study, please visit our website at www.rochesterproject.org or contact us at info@rochesterproject.org. Our website also provides access to an introductory video in English and Spanish.

Epilepsy-related mortality is low in children: a 30-year population-based study in Olmsted County, MN

PURPOSE

Epilepsy is a common childhood neurologic disorder, affecting 0.5-1% of children. Increased mortality occurs due to progression of underlying disease, seizure-related accidents, suicide, status epilepticus, aspiration during seizures, and sudden unexplained death in epilepsy (SUDEP). Previous studies show mortality rates of 2.7-6.9 per 1,000 person-years. Potential risk factors include poor seizure control, intractable epilepsy, status epilepticus, tonic-clonic seizures, mental retardation, and remote symptomatic cause of epilepsy. Few population-based studies of mortality and SUDEP in childhood-onset epilepsy have been published. The purpose of this study is to report mortality and SUDEP from a 30-year population-based cohort of children with epilepsy.

METHODS

The Medical Diagnostic Index of the Rochester Epidemiology Project was searched for all codes related to seizure and convulsion in children living in Olmsted County, Minnesota and of ages birth through 17 years from 1980 through 2009. The medical records of these children were reviewed to identify all those with new-onset epilepsy, and to abstract other baseline and follow-up information. Potential risk factors including seizure type, epilepsy syndrome, history of status epilepticus, the presence and severity of neurologic impairment, and epilepsy outcome was reviewed. Epilepsy outcome was characterized by seizure frequency, number of antiseizure medications (antiepileptic drugs, AEDs) used, and number of AEDs failed due to lack of efficacy, and epilepsy intractability at 1 year and 2, 3, 5, 10, 15, and 20 years after epilepsy onset. We followed all children through their most recent visit to determine vital status, cause of death, and whether autopsy was performed.

KEY FINDINGS

From 1980 to 2009, there were 467 children age birth through 17 years diagnosed with epilepsy while residents of Olmsted County, Minnesota, and who had follow-up beyond the time of epilepsy diagnosis. Children were followed for a median of 7.87 years after the time of diagnosis (range 0.04-29.49 years) for a total of 4558.5 person-years. Sixteen (3.4%) of the children died, or 3.51 deaths per 1,000 person-years. Two deaths were epilepsy related (12.5%) for a rate of 0.44 per 1,000 person-years. One of these children died of probable SUDEP and one died of aspiration during a seizure. The remaining 14 deaths (87.5%) were caused by other complications of underlying disease. Several risk factors for mortality were found, including abnormal cognition, abnormal neurologic examination, structural/metabolic etiology for epilepsy, and poorly controlled epilepsy.

SIGNIFICANCE

Although mortality in children with epilepsy was higher than what would be expected in the general pediatric population, death occurred significantly more in children with neurologic impairment and poorly controlled epilepsy. Epilepsy-related death, including SUDEP, was rare and mortality due to epilepsy alone was similar to the expected mortality in the general population (observed deaths = 2, expected deaths = 1.77; standardized mortality ratio 1.13, 95% confidence interval 0.19-3.73, p = 0.86). By contrast, most children died of complications of the underlying neurologic disease or unrelated disease rather than the epilepsy.

Metabolic markers or conditions preceding Parkinson's disease: a case-control study

Several metabolic markers or conditions have been explored as possible risk or protective factors for Parkinson's disease (PD); however, results remain conflicting. We further investigated these associations using a case-control study design. We used the medical records-linkage system of the Rochester Epidemiology Project to identify 196 subjects who developed PD in Olmsted County, Minnesota, from 1976 through 1995. Each incident case was matched by age (±1 year) and sex to a general population control. We reviewed the complete medical records of cases and controls in the medical records-linkage system to abstract information about body mass index (BMI), cholesterol level, hypertension, and diabetes mellitus preceding the onset of PD (or the index year). There were no significant differences between cases and controls for the metabolic markers or conditions investigated. No significant associations were found using 2 cutoffs for BMI level (BMI ≥ 25 or BMI ≥ 30 kg/m(2) ) and 3 cutoffs for cholesterol levels (>200, >250, or >300 mg/dL). Neither a diagnosis of hypertension or the documented use of antihypertensive medications was significantly associated with the subsequent risk of PD (odds ratio [OR], 1.00; 95% confidence interval [CI], 0.65-1.54; P = .99) nor was a diagnosis of diabetes mellitus or the use of glucose-lowering medications (OR, 0.77; 95% CI, 0.37-1.57; P = .47). Our study, based on historical information from a records-linkage system, does not support an association between BMI, cholesterol level, hypertension, or diabetes mellitus with later development of PD.

Generalizability of epidemiological findings and public health decisions: an illustration from the Rochester Epidemiology Project

OBJECTIVE

To illustrate the problem of generalizability of epidemiological findings derived from a single population using data from the Rochester Epidemiology Project and from the US Census.

METHODS

We compared the characteristics of the Olmsted County, Minnesota, population with the characteristics of populations residing in the state of Minnesota, the Upper Midwest, and the entire United States.

RESULTS

Age, sex, and ethnic characteristics of Olmsted County were similar to those of the state of Minnesota and the Upper Midwest from 1970 to 2000. However, Olmsted County was less ethnically diverse than the entire US population (90.3% vs 75.1% white), more highly educated (91.1% vs 80.4% high school graduates), and wealthier ($51,316 vs $41,994 median household income; 2000 US Census data). Age- and sex-specific mortality rates were similar for Olmsted County, the state of Minnesota, and the entire United States.

CONCLUSION

We provide an example of analyses and comparisons that may guide the generalization of epidemiological findings from a single population to other populations or to the entire United States.

Hysterectomy, oophorectomy, estrogen, and the risk of dementia

Background

The long-term cognitive effects of hysterectomy and oophorectomy remain controversial. Objective: To explore the association of hysterectomy and oophorectomy with the subsequent risk of cognitive impairment or dementia.

Methods

We combined the results from two cohort studies graphically and conducted additional analyses.

Results

Combined results from the Mayo Clinic Cohort Study of Oophorectomy and Aging and from a Danish nationwide cohort study suggest that the extent of gynecologic surgery may correlate with a stepwise increase in the risk of cognitive impairment or dementia. Compared with women with no gynecologic surgeries, the risk of cognitive impairment or dementia was increased in women who had hysterectomy alone, further increased in women who had hysterectomy with unilateral oophorectomy, and further increased in women who had hysterectomy with bilateral oophorectomy. The risk increased with younger age at the time of the surgery.

Conclusion

We hypothesize that both hysterectomy and oophorectomy may have harmful brain effects via direct endocrinological mechanisms or other more complex mechanisms. Estrogen deficiency appears to play a key role in these associations, and estrogen therapy may partly offset the negative effects of the surgeries.

A single dose of neuron-binding human monoclonal antibody improves spontaneous activity in a murine model of demyelination

Our laboratory demonstrated that a natural human serum antibody, sHIgM12, binds to neurons in vitro and promotes neurite outgrowth. We generated a recombinant form, rHIgM12, with identical properties. Intracerebral infection with Theiler's Murine Encephalomyelitis Virus (TMEV) of susceptible mouse strains results in chronic demyelinating disease with progressive axonal loss and neurologic dysfunction similar to progressive forms of multiple sclerosis. To study the effects of rHIgM12 on the motor function of TMEV-infected mice, we monitored spontaneous nocturnal activity over many weeks. Nocturnal behavior is a sensitive measure of rodent neurologic function because maximal activity changes are expected to occur during the normally active night time monitoring period. Mice were placed in activity boxes eight days prior to treatment to collect baseline spontaneous activity. After treatment, activity in each group was continuously recorded over 8 weeks. We chose a long 8-week monitoring period for two reasons: (1) we previously demonstrated that IgM induced remyelination is present by 5 weeks post treatment, and (2) TMEV-induced demyelinating disease in this strain progresses very slowly. Due to the long observation periods and large data sets, differences among treatment groups may be difficult to appreciate studying the original unfiltered recordings. To clearly delineate changes in the highly fluctuating original data we applied three different methods: (1) binning, (2) application of Gaussian low-pass filters (GF) and (3) polynomial fitting. Using each of the three methods we showed that compared to control IgM and saline, early treatment with rHIgM12 induced improvement in both horizontal and vertical motor function, whereas later treatment improved only horizontal activity. rHIgM12 did not alter activity of normal, uninfected mice. This study supports the hypothesis that treatment with a neuron-binding IgM not only protects neurons in vitro, but also influences functional motor improvement.

Clinical failure of botulinum toxin A in movement disorders

OBJECTIVE

Botulinum toxin (BTX) injections have been used extensively in medicine; however, little is known about the factors predicting the loss of effectiveness of botulin toxin.

METHODS

Using a clinical database, we identified 401 subjects who had been treated for movement disorders from 1998 through 2010 with onabotulinumtoxin A (BTX A) or who switched from BTX A to rimabotulinumtoxin B (BTX B). We compared patients who switched from type A to type B with patients using type A only with regard to number of visits, total number of injections, number of initial and final sites, number of initial units used, and duration of treatments.

RESULTS

We observed that patients who switched from BTX A to B had a significantly higher number of initial injection sites than patients with BTX A only (BTX A to B median = 8.5; BTX A median = 6; p for difference = 0.006), had a higher number of final sites (BTX A to B median = 9 BTX A median = 7; p = 0.01), and were also more likely to have multiple reasons for injection (BTX A to B = 25.0%; botulin toxin A = 5.3%; p = 0.01). We did not find significant differences between groups based on the other variables.

CONCLUSIONS

Our findings suggest that higher number of sites rather than higher number of units or years of treatment are associated with the loss of effectiveness to BTX A. It is possible that the loss of effectiveness to the BTX is more strongly elicited when the injections are widely diffuse.

Use of a medical records linkage system to enumerate a dynamic population over time: the Rochester epidemiology project

The Rochester Epidemiology Project (REP) is a unique research infrastructure in which the medical records of virtually all persons residing in Olmsted County, Minnesota, for over 40 years have been linked and archived. In the present article, the authors describe how the REP links medical records from multiple health care institutions to specific individuals and how residency is confirmed over time. Additionally, the authors provide evidence for the validity of the REP Census enumeration. Between 1966 and 2008, 1,145,856 medical records were linked to 486,564 individuals in the REP. The REP Census was found to be valid when compared with a list of residents obtained from random digit dialing, a list of residents of nursing homes and senior citizen complexes, a commercial list of residents, and a manual review of records. In addition, the REP Census counts were comparable to those of 4 decennial US censuses (e.g., it included 104.1% of 1970 and 102.7% of 2000 census counts). The duration for which each person was captured in the system varied greatly by age and calendar year; however, the duration was typically substantial. Comprehensive medical records linkage systems like the REP can be used to maintain a continuously updated census and to provide an optimal sampling framework for epidemiologic studies.