Increased falling as a risk factor for fracture among older women: the study of osteoporotic fractures

More frequent falling is associated with a higher risk of fracture among older women, but it is not known whether an increased rate of falling, independent of the average rate, also increases fracture risk. The authors examined the relation between an increase in the rate of falls during the first 4 years of follow-up and the subsequent fracture rate, reported for a median of 6.3 years (1986-1998), in 9,106 US women aged 65 years or more. Women in the upper quartile of increasing falls (>0.44 falls/year/year) had greater risks of subsequent hip fracture (rate ratio = 1.42, 95% confidence interval: 0.99, 2.04) and fracture of the proximal humerus (rate ratio = 1.79, 95% confidence interval: 1.08, 2.95) than women without an increase in falls, after adjustment for age, average rate of falls over 4 years, and known risk factors for fracture. Risks of distal forearm, ankle, or foot fracture were not elevated. The associations between fracture risk and increasing falls were not accounted for by baseline physical or cognitive function. An increase in the rate of falls, independent of the average rate, may be associated with a higher risk of frailty (hip and proximal humerus) fractures but not fractures at other sites.

Idiopathic Pulmonary Fibrosis*

Idiopathic pulmonary fibrosis (IPF) is a relentlessly progressive and typically fatal interstitial lung disease. Besides its grave natural history and prognosis, three aspects of IPF challenge clinicians and investigators: (1) recent changes in the conceptual framework and definition of IPF complicate interpretation of prior clinical investigations; (2) while most patients with suspected IPF do not undergo open-lung biopsy, clinical definitions that do not include biopsy criteria have not been validated prospectively; and (3) available treatments have not been shown to be effective. To optimize clinical care and facilitate clinical investigation, a major goal of IPF research should be to develop validated sets of clinical diagnostic and prognostic criteria. Studies have shown the diagnostic value of high-resolution CT scans and identified important prognostic variables; many of these observations await prospective validation. While previous therapeutic studies have been limited by small sample sizes, lack of a placebo control group, and insufficient attention to patient-centered outcomes, the recent study of interferon gamma-1b demonstrated the feasibility of a large-scale, multicenter clinical trial in IPF. In this article, we discuss how overcoming challenges in IPF research will enable future investigators to conduct well-designed observational studies and clinical trials, whose meaningful results will advance our understanding of IPF, its management, and its impact on patients' lives.

Inconsistencies between self-reported ethnicity and ethnicity recorded in a health maintenance organization

PURPOSE

Information on patient ethnicity in hospital admissions databases is often used in epidemiologic and health services research. However, the extent of consistency of these data with self-reported ethnicity is not well studied, particularly for specific Asian subgroups. We examined agreement between ethnicity in records of a sample of members of five Northern California Kaiser Permanente medical centers with self-reported ethnicity.

METHODS

Subjects were 3168 cases and 2413 controls aged 45 years and older from a study of fractures. Ethnicity recorded in the Kaiser admissions database (primarily inpatient) was compared with self-reported ethnicity from the study interviews.

RESULTS

Among study subjects with available Kaiser ethnicity, sensitivities and positive predictive values of the Kaiser classification were high among blacks (0.95 for both measures) and whites (0.98 and 0.94, respectively), slightly lower among Asians (0.88 and 0.95, respectively), and considerably lower among Hispanics (0.55 and 0.81, respectively) and American Indians (0.47 and 0.50, respectively). Among Asian subgroups, the proportion classified as Asian was high among Chinese (0.94) and Japanese (0.99) but lower among Filipinos (0.79) and other Asians (0.74). Among the 228 (4%) subjects who self-identified with multiple ethnicities, 13 of 18 white + Hispanic subjects were classified as being white, and of the 77 subjects identifying as part American Indian, only one was classified as being American Indian in the Kaiser database.

CONCLUSIONS

Given the importance of ethnicity information, medical facilities should be encouraged to adopt policies toward collecting high quality data.

Immigration and acculturation in relation to health and health-related risk factors among specific Asian subgroups in a health maintenance organization

OBJECTIVES

We sought to determine how risk factors for disease vary among Asian subgroups.

METHODS

Using data from a case-control study conducted at Northern California Kaiser Medical Centers (from 1996 to 2001), we compared prevalence of selected risk factors among Asian subgroups and evaluated the associations of these risk factors with sociodemographic factors.

RESULTS

Chinese and Japanese patients had a lower body mass index (kg/m(2)) than did other Asians. In all subgroups, being born in the United States was associated with having a body mass index greater than 25 kg/m(2). Compared with other Asians, more Japanese and multiple-race Asians smoked, and more Filipino and multiple-race Asian smokers started smoking at 18 years or younger. Filipinos and multiple-race Asians also were more likely to report diabetes.

CONCLUSIONS

These data support the importance of efforts to distinguish among Asian subgroups in public health practice and research.

Risk factors for proximal humerus fracture

This case-control study of proximal humerus fracture included 448 incident female and male cases and 2,023 controls aged 45 years or older identified in five Northern California Kaiser Permanente Medical Centers in 1996-2001. Data were collected by using an interviewer-administered questionnaire. Some factors related to low bone mass, including number of fractures since age 45 years and low dietary calcium intake, were associated with increased risks of fracture, and factors thought to protect against bone loss, such as menopausal hormone therapy and calcium carbonate tablet use, were associated with reduced risks. Fall-related risk factors included previous falls, diabetes mellitus, and difficulty walking in dim light. Possible fall-related risk factors suggested for the first time in this study were seizure medication use (adjusted odds ratio (OR) = 2.80, 95% confidence interval (CI): 1.45, 5.42), depression (OR = 1.34, 95% CI: 0.98, 1.84), almost always using a hearing aid (OR = 1.92, 95% CI: 1.12, 3.31 vs. never prescribed), and left-handedness (OR = 2.36, 95% CI: 1.51, 3.68 vs. right-handedness). Difficulty with activities of daily living and lack of physical activity tended to be associated with increased risk. Prevention of falls among frail, osteoporotic persons would likely reduce the frequency of proximal humerus fracture.

Effect of alendronate on bone mineral density and biochemical markers of bone turnover in type 2 diabetic women: the fracture intervention trial

OBJECTIVE

Alendronate sodium (ALN) increases bone mineral density (BMD) in heterogeneous populations of postmenopausal women, but its effect is unknown in women with type 2 diabetes. The objective of this project was to compare changes in BMD during 3 years of ALN treatment versus placebo in diabetic women.

RESEARCH DESIGN AND METHODS

We used data from the Fracture Intervention Trial, a randomized blinded placebo-controlled trial conducted at 11 centers in which 6458 women aged 54-81 years with a femoral neck BMD of <or=0.68 g/cm(2) were randomly assigned to either placebo or 5 mg/day ALN for 2 years, followed by 10 mg/day for the remainder of the trial. BMD was measured by dual-energy X-ray absorptiometry. Type 2 diabetes (n = 297) was defined by self-report, use of insulin or other hypoglycemic agents, or a random nonfasting glucose value >or=200 mg/dl.

RESULTS

In diabetic women, 3 years of ALN treatment was associated with increased BMD at all sites studied, including 6.6% at the lumbar spine and 2.4% at the hip, whereas women in the placebo group experienced a decrease in BMD at all sites except the lumbar spine. The safety/tolerability of ALN was similar to placebo, except for abdominal pain, which was more likely in the ALN group.

CONCLUSIONS

ALN increased BMD relative to placebo in older women with type 2 diabetes and was generally well tolerated as a treatment for osteoporosis. Increases in BMD with ALN therapy compared with placebo were similar between women with and without diabetes.

Bias in Completeness of Birthplace Data for Asian Groups in a Population-Based Cancer Registry (United States)

Data on place of birth are routinely collected by population-based cancer registries in the United States and are used to study effects of immigration on cancer patterns in Asian migrants, who comprise about a quarter of the US immigrant population. However, the quality of this research, which has the potential for informing cancer etiology and control, is unclear because registry birthplace information is incomplete, and its accuracy has not been examined. We quantified misclassification of birthplace data for Asian cancer patients in the Greater Bay Area Cancer Registry in northern California by comparing registry birthplace information with self-reported birthplace from interview, and then identified sociodemographic and hospital characteristics associated with birthplace completeness and misclassification. Of the 1836 eligible Asian patients, 649 (35%) had unrecorded registry birthplace. For all except Vietnamese, these persons were less likely than those with recorded birthplace to be foreign-born (OR = 0.5, 95% CI = 0.4-0.7), to be diagnosed in public than private hospitals (OR = 0.7, 95% CI = 0.5-0.8) and in teaching than non-teaching hospitals (OR = 0.8, 95% CI = 0.6-1.1), and were more likely to have been diagnosed at a large regional health maintenance organization (OR = 1.7, 95% CI = 1.3-2.2) and after 1995 (OR = 1.6, 95% CI = 1.1-2.1). Among Asians with registry birthplace information (n = 1187), sensitivity and predictive value positive for birthplace exceeded 90% for both US- and foreign-born, except for Japanese (predictive value positive = 85.7%). Among US-born Asians, those misclassified as foreign-born were more likely than those correctly classified to prefer a non-English primary language (OR = 29.4, 95% CI = 1.9-459.9). These results suggest that cancer registry birthplace data for Asians should not be used if they continue to be differentially incomplete for a large proportion of the subjects.

Characteristics of fallers who fracture at the foot, distal forearm, proximal humerus, pelvis, and shaft of the tibia/fibula compared with fallers who do not fracture

This case-control study examined the relation of circumstances of falls and characteristics of fallers with risk of fractures at five sites among persons 45 years of age or older from five Kaiser Permanente Medical Centers in Northern California from 1996 to 2001. Included were distal forearm (n = 1,016), foot (n = 574), proximal humerus (n = 467), pelvis (n = 150), and shaft of the tibia/fibula (n = 141) cases who fell at the time of their fracture, and controls (n = 512) who reported falling in the year before the interview but did not fracture. Interviewers collected information by using a standardized questionnaire. Medium-/high-heeled shoes and shoes with a narrow heel increased the risk of all fractures, and slip-on shoes (adjusted odds ratio = 2.3, 95% confidence interval: 1.4, 4.0) and sandals (adjusted odds ratio = 3.1, 95% confidence interval: 1.5, 6.3) increased the risk of foot fractures. Falling from more than a standing height increased the risk of all fractures by two- to fivefold, while breaking the fall was associated with lower risks of all fractures except the distal forearm. Physical activity and hormone therapy were associated with lower risks of most fractures. These results suggest ways in which risks of fractures in older persons can be reduced.

Left-handedness as a risk factor for fractures

Left-handedness has been associated with increased fracture risk in a small number of previous studies. This study reports risks for fractures at the proximal humerus, distal forearm, pelvis, foot, and shaft of the tibia/fibula according to handedness in a case-control study conducted from October 1996 to May 2001 among members of Northern California Kaiser Permanente. Handedness was assessed by questionnaire for 2,841 cases and 2,192 controls, and subjects were categorized as left-handed, right-handed, ambidextrous, or forced to switch from the left to the right hand. Compared to right-handedness, left-handedness was most strongly associated with an increased risk for proximal humerus fractures (adjusted odds ratio (OR)=2.00, 95% confidence interval (CI) 1.33 to 3.01) and less definitively with fractures of the distal forearm (adjusted OR=1.28, 95% CI 0.92 to 1.80), foot (adjusted OR=1.17, 95% CI 0.82 to 1.65), and pelvis (adjusted OR=1.40, 95% CI 0.71 to 2.74). Ambidextrous individuals had elevated risks for fractures of the distal forearm (adjusted OR=2.99, 95% CI 1.42 to 6.30), foot (adjusted OR=2.59, 95% CI 1.13 to 5.97), shaft of the tibia/fibula (adjusted OR=3.91, 95% CI 1.01 to 15.17), and proximal humerus (adjusted OR=2.37, 95% CI 0.85 to 6.65) when compared with right-handed individuals. Those individuals forced to use the right hand demonstrated no increased risk for fractures at any site. These results suggest that handedness does influence fracture risk, but the reasons for this increased risk are unclear.

Hormone replacement therapy and risk for foot, distal forearm, proximal humerus, and pelvis fractures

This case-control epidemiologic study examines the relationship between hormone replacement therapy (HRT) and risk for fractures of four sites among women 45 years of age and older. From October 1996 to May 2001, incident patients with distal forearm ( n=744), foot ( n=618), proximal humerus ( n=331), and pelvis ( n=109) fractures were recruited from five Kaiser Permanente Medical Centers in northern California. Controls ( n=1617) were selected at random from the same five medical centers over the same time period within strata defined by 5-year age group, gender, and white versus nonwhite or unknown recorded race/ethnicity. Trained interviewers collected information using a standardized questionnaire. Compared with postmenopausal women who never used HRT, postmenopausal women currently using HRT for at least 3 months had a decreased risk of fracture at the distal forearm (adjusted OR=0.55, 95% CI: 0.43, 0.72), proximal humerus (adjusted OR=0.51, 95% CI: 0.36, 0.74), and pelvis (adjusted OR=0.51, 95% CI: 0.27, 0.95), but not the foot (adjusted OR=1.05, 95% CI: 0.81, 1.35). Past use of HRT for more than 7 years also appeared to be associated with a reduced risk of fracture at the distal forearm and proximal humerus. The longer a woman went without HRT after her last menstrual period, the greater her risk of fracture in the distal forearm, proximal humerus, and pelvis. The findings of this study support long-term, current use of HRT for the prevention of osteoporotic fractures, but other risks and benefits also need to be considered.

Disordered eating, menstrual irregularity, and bone mineral density in female runners

PURPOSE

To examine the relationships between disordered eating, menstrual irregularity, and low bone mineral density (BMD) in young female runners.

METHODS

Subjects were 91 competitive female distance runners aged 18-26 yr. Disordered eating was measured by the Eating Disorder Inventory (EDI). Menstrual irregularity was defined as oligo/amenorrhea (0-9 menses per year). BMD was measured by dual x-ray absorptiometry.

RESULTS

An elevated score on the EDI (highest quartile) was associated with oligo/amenorrhea, after adjusting for percent body fat, age, miles run per week, age at menarche, and dietary fat, (OR [95% CI]: 4.6 [1.1-18.6]). Oligo/amenorrheic runners had lower BMD than eumenorrheic runners at the spine (-5%), hip (-6%), and whole body (-3%), even after accounting for weight, percent body fat, EDI score, and age at menarche. Eumenorrheic runners with elevated EDI scores had lower BMD than eumenorrheic runners with normal EDI scores at the spine (-11%), with trends at the hip (-5%), and whole body (-5%), after adjusting for differences in weight and percent body fat. Runners with both an elevated EDI score and oligo/amenorrhea had no further reduction in BMD than runners with only one of these risk factors.

CONCLUSION

In young competitive female distance runners, (i) disordered eating is strongly related to menstrual irregularity, (ii) menstrual irregularity is associated with low BMD, and (iii) disordered eating is associated with low BMD in the absence of menstrual irregularity.

Oral contraceptives and bone mineral density in white and black women in CARDIA. Coronary Risk Development in Young Adults

To examine whether exposure to oral contraceptives (OCs) is associated with bone mineral density (BMD) in young women, we studied, cross-sectionally and longitudinally, 216 white and 260 black women enrolled in the Coronary Artery Risk Development in Young Adults (CARDIA) study. Spine, hip and whole body BMDs were measured by dual-energy X-ray absorptiometry (DXA) when the women were aged 25-37 years, and whole body BMD was remeasured in 369 of the women 3 years later. A comprehensive history of OC use, including dose of ethinyl estradiol (estrogen) and duration of use, was determined from an interviewer-administered questionnaire. After adjustment for other relevant variables, we found that cumulative estrogen from OCs (mg) explained 4.0% of the variation in spine BMD ( p = 0.024) among white women, but did not explain any of the variance in BMD in black women. Cumulative OC estrogen was associated with a decreased risk for low bone density (lowest quartile) at the spine, hip and whole body in white women. The odds ratios (95% CIs) comparing women in the highest quartile of cumulative OC estrogen with those in the lowest quartile were, at the spine: 0.08 (0.02, 0.46); at the hip: 0.23 (0.06, 0.87); and at the whole body: 0.37 (0.11, 1.26). OC exposure was not related to low bone density in black women. OCs did not predict longitudinal changes in whole body BMD in either race. These results suggest that exposure to the estrogen from OCs during the premenopausal years may have a small beneficial effect on the skeleton in white women. Benefit is proportional to the cumulative estrogen exposure, suggesting that previous cross-sectional studies that considered OC use as a dichotomous variable may have lacked the power to detect an association.

Ethnic variation in bone density in premenopausal and early perimenopausal women: effects of anthropometric and lifestyle factors

Bone mineral density (BMD) and fracture rates vary among women of differing ethnicities. Most reports suggest that BMD is highest in African-Americans, lowest in Asians, and intermediate in Caucasians, yet Asians have lower fracture rates than Caucasians. To assess the contributions of anthropometric and lifestyle characteristics to ethnic differences in BMD, we assessed lumbar spine and femoral neck BMD by dual-energy x-ray absorptiometry in 2277 (for the lumbar spine) and 2330 (for the femoral neck) premenopausal or early perimenopausal women (mean age, 46.2 yr) participating in the Study of Women's Health Across the Nation. Forty-nine percent of the women were Caucasian, 28% were African-American, 12% were Japanese, and 11% were Chinese. BMDs were compared among ethnic groups before and after adjustment for covariates. Before adjustment, lumbar spine and femoral neck BMDs were highest in African-American women, next highest in Caucasian women, and lowest in Chinese and Japanese women. Unadjusted lumbar spine and femoral neck BMDs were 7-12% and 14-24% higher, respectively, in African-American women than in Caucasians, Japanese, or Chinese women. After adjustment, lumbar spine and femoral neck BMD remained highest in African-American women, and there were no significant differences between the remaining groups. When BMD was assessed in a subset of women weighing less than 70 kg and then adjusted for covariates, lumbar spine BMD became similar in African-American, Chinese, and Japanese women and was lowest in Caucasian women. Adjustment for bone size increased values for Chinese women to levels equal to or above those of Caucasian and Japanese women. Among women of comparable weights, there are no differences in lumbar spine BMD among African-American, Chinese, and Japanese women, all of whom have higher BMDs than Caucasians. Femoral neck BMD is highest in African-Americans and similar in Chinese, Japanese, and Caucasians. These findings may explain why Caucasian women have higher fracture rates than African-Americans and Asians.

Foot problems as risk factors of fractures

This case-control study examines whether foot problems are risk factors of fractures of five sites among people aged 45 years or older at six Kaiser Permanente Medical Centers in northern California. From October 1996 to May 2001, interviewers collected information through a standardized questionnaire. Incident cases of distal forearm (n = 1,000), foot (n = 827), proximal humerus (n = 448), shaft of the tibia/fibula (n = 168), and pelvis (n = 172) fractures and 1,913 controls from the same medical centers were included. After adjustment for potential confounders and for each additional foot problem, the odds of a foot fracture increased by 8% (adjusted odds ratio = 1.08, 95% confidence interval: 1.03, 1.13). In contrast, each additional foot problem was associated with a reduction in the odds of a forearm fracture (adjusted odds ratio = 0.93, 95% confidence interval: 0.89, 0.98). In general, foot problems were not related to fractures of other sites, although diabetes, which may result in foot problems, increased the odds of a proximal humerus fracture (adjusted odds ratio = 1.65, 95% confidence interval: 1.20, 2.26). If these findings are supported by data from other studies, preventive measures to retard the development of foot problems could reduce the incidence of foot fractures.

Characteristics associated with recent recreational exercise among women 20 to 44 years of age

Data on 1,501 control women from a multi-center, population-based, case-control study of breast cancer were used to examine characteristics associated with recreational exercise during the year prior to the interview among women 20 to 44 years of age. In a univariate analysis, higher levels of recreational exercise were associated with: higher education; higher family income; white race; previous participation in recreational exercise above the median level at ages 12 to 13 and at age 20; being nulliparous; ever lactating; being a never or past smoker; having a low current Quetelet's index (QI: weight in kilograms divided by height in meters squared); and living in Atlanta or Seattle (compared to New Jersey). In a multiple linear regression model, independent predictors of higher levels of recreational exercise were: participation in higher levels of exercise at 20 years of age; having a low current QI; and never having smoked. Though all women should be encouraged to participate in exercise, these findings identity subgroups of women that may need targeting when developing exercise intervention programs.

Household appliance use and residential exposure to 60-hz magnetic fields

We characterized the distribution of exposure to magnetic fields (MFs) during daily activities and during household appliance use, and estimated the relative contribution of various activities and appliances to total daily exposure. One hundred sixty-two subjects provided information on their patterns of appliance use and wore personal monitors for 24 h to collect MF exposure data. Of total exposure, 27% accumulated while subjects were in bed; 41% while at home but not in bed; 9% at work; and 24% elsewhere. Less than 2% of the total MF exposure accumulated during the use of each of the eight individual appliances considered, except computers, during the use of which 9% of the total exposure accumulated. Of the time subjects spent at exposure levels higher than 2 microT, 8% accumulated while they were using microwave ovens, and 4% and 3% while using computers and electric stoves, respectively. Mean MF measurements tended to be lowest when subjects were in bed and highest at work and during the use of microwave ovens, coffee grinders, hair dryers, and electric shavers. Results from questionnaires on household appliance use in the past year were not useful in predicting the total mean exposure level and over-threshold exposures measured by 24-h personal monitors. Significant MF exposure accumulates at home, at work, and elsewhere; therefore, accurate exposure assessment needs to consider residential, occupational, and other sources together. Questionnaire-based information on appliance use has limited value in the assessment of average and over-threshold exposure to MFs.

Relation of demographic and lifestyle factors to symptoms in a multi-racial/ethnic population of women 40-55 years of age

A community-based survey was conducted during 1995-1997 of factors related to menopausal and other symptoms in a multi-racial/ethnic sample of 16,065 women aged 40-55 years. Each of seven sites comprising the Study of Women's Health across the Nation (SWAN) surveyed one of four minority populations and a Caucasian population. The largest adjusted prevalence odds ratios for all symptoms, particularly hot flashes or night sweats (odds ratios = 2.06-4.32), were for women who were peri- or postmenopausal. Most symptoms were reported least frequently by Japanese and Chinese (odds ratios = 0.47-0.67 compared with Caucasian) women. African-American women reported vasomotor symptoms and vaginal dryness more (odds ratios = 1.17-1.63) but urine leakage and difficulty sleeping less (odds ratios = 0.64-0.72) than Caucasians. Hispanic women reported urine leakage, vaginal dryness, heart pounding, and forgetfulness more (odds ratios = 1.22-1.85). Hot flashes or night sweats, urine leakage, and stiffness or soreness were associated with a high body mass index (odds ratios = 1.15-2.18 for women with a body mass index > or =27 vs. 19-26.9 kg/m2). Most symptoms were reported most frequently among women who had difficulty paying for basics (odds ratios = 1.15-2.05), who smoked (odds ratios = 1.21-1.78), and who rated themselves less physically active than other women their age (odds ratios = 1.24-2.33). These results suggest that lifestyle, menstrual status, race/ethnicity, and socioeconomic status affect symptoms in this age group.

Reliability of proxy-reported and self-reported household appliance use

Exposure assessment presents a major challenge for studies evaluating the association between household exposure to electric and magnetic fields and adverse health outcomes, especially the reliance on proxy respondents when study subjects themselves have died. We evaluated the reliability of proxy- and self-reported household appliance exposure. We recruited 92 healthy couples through either random-digit dialing or newspaper advertisements. Trained interviewers administered questionnaires to each member of a couple independently to assess the reliability of proxy-reported household appliance use. Eighty-five couples completed a second interview 2 months later to assess the reliability of self-reported appliance use. Reliability of proxy-reported appliance exposure was good when we inquired about having any exposure to each of the eight indicator appliances during the past year (range of kappa coefficients = 0.63-0.85; median = 0.76) but was lower with increased time to recall or increased detail. Reliability of self respondents reporting 2 months apart was excellent (range of kappa coefficients = 0.75-0.94; median = 0.87) for having any exposure to the eight indicator appliances during the past year, but reliability was again lower with increased detail. When we used self reports at the first interview as the standard, little systematic over- or underreporting occurred for proxy respondents or for self respondents reporting 2 months later. Because this study did not include cases of specific disease, these findings of no systematic differences in reporting do not refer to case or control status. In summary, reliability of self respondents' reports of appliance use is very good for recent time periods and good for broad aspects of exposure in distant time periods. Proxy respondents can provide information regarding broad aspects of appliance exposure in the past year, but detailed aspects of exposure or exposure in more distant time periods is not reliable.

Relationship of neurological function and age in older women. The study of osteoporotic fractures

The decline of neurological and neuromuscular function with age in older women and in subgroups of older women with selected risk factors for poor function is described using cross- sectional analyses of data on 8,080 women from the multicenter Study of Osteoporotic Fractures. All twelve performance-based tests of muscle strength, balance, gait, somatosensory discrimination and reaction time declined with increasing age. On a percentage scale, vibration threshold declined the most rapidly with age. Participants who were smokers, physically inactive, nonconsumers of alcohol, diabetics and more frequent fallers had poorer age-adjusted performance than those without these attributes. However, with a few exceptions, the rate of decline in performance with age for those with and without these characteristics did not differ significantly.

Oral contraceptive and benign ovarian tumors

Whether use of combined oral contraceptives (OC) protects against benign ovarian tumors is unknown. A case-control study of pathologically confirmed benign ovarian tumors was conducted in the New York City area and included cases diagnosed from January 1, 1992, to December 31, 1993, and controls identified by random digit dialing. There were 196 cases with serous adenomas, 176 with teratomas, 311 with endometriomas, and 65 with mucinous adenomas. Interview data were used to determine contraceptive use. Ever use of OC was associated with a decreased risk of these benign tumors (age- and hospital-adjusted odds ratio = 0.79, 95% confidence interval: 0.60, 1.05). In histologic subgroup analyses, the risk of ovarian tumors was reduced for both current and past OC users. Among tumor subtypes, the risk reduction was greatest for women who had endometriotic lesions. The risk reduction also was greater for women who had used OC for more than 24 months. Protection against benign ovarian tumors may be an additional noncontraceptive benefit of OC use.

Falls in older Mexican-American women

OBJECTIVE

To determine the frequency of falls and identify risk factors for falls among older Mexican-American women.

DESIGN

A prospective cohort study with an average follow-up of 2.7 years.

SETTING

A clinical center at the Palo Alto Veterans Affairs Medical Center, California.

PARTICIPANTS

152 community-dwelling Mexican-American Caucasian women aged 59 years or older.

OUTCOME MEASURES

Falls and injurious falls, as determined by monthly telephone interviews.

RESULTS

The rate of falls was 508 per 1000 person-years (95% confidence interval (CI), 440-577). Injurious falls requiring medical attention occurred at a rate of 79 per 1000 person-years (95% CI, 52-107). Factors that were associated independently with an increased risk of falling were older age, a history of arthritis or rheumatism, a history of high thyroid, having fainted at least once in the year before baseline, current use of psychotropic medications, and walking fewer than 5 blocks a day. Those persons with an average time for the chair stand test had a lower risk of falling than those with the slowest times or the fastest times.

CONCLUSIONS

The frequency of falls and injurious falls in this cohort of 152 relatively acculturated, healthy, older Mexican-American women was similar or slightly higher than previously reported rates for non-Hispanic Caucasian(s). Many of the factors associated with falls in this study were similar to those reported for non-Hispanic Caucasian women, suggesting that fall prevention measures tested mainly among non-Hispanic Caucasian women would also be appropriate for Mexican-American women.

International variation in the incidence of hip fractures: cross-national project on osteoporosis for the World Health Organization Program for Research on Aging

A cross-national study of hip fracture incidence was carried out in five geographic areas--Beijing, China; Budapest, Hungary; Hong Kong; Porto Alegre, Brazil; and Reykjavik, Iceland--during the years 1990-1992. Cases of hip fracture among women and men of age 20 years and older were identified using hospital discharge data in conjunction with medical records, operating room logs, and radiology logs. Estimated incidence rates varied widely, with Beijing reporting the lowest rates (age-adjusted rate per 100,000 population for men 20 years and older = 45.4; women = 39.6) and Reykjavik the highest rates (man = 141.3; women = 274.1). Rates were higher for women than for men in every area except Beijing. In every area except Budapest, review of the operating room or radiology logs identified additional cases that were not reported in the discharge list, increasing the estimated number of hip fractures by 11% to 62%, depending on the area. Review of medical records identified miscoding of hip fractures (ICD 9820) as 'shaft of femur and other femur fractures' (ICD 9821) in the discharge lists of every area except Budapest, increasing the estimated number of hip fractures by 1% to 30%. The final estimates of hip fracture incidence taking into account all investigated sources of undercount and overcount ranged from 15% lower to 89% higher than an estimate based on the discharge diagnoses alone. Although these results indicate substantial limitations in relying on hospital discharge data alone to estimate hip fracture incidence rates, the extent of errors found in the discharge lists is smaller than the large international variation found here and previously reported in incidence rates. The findings support the conclusion that the differences reported among countries mainly reflect genuine variation in the hip fracture incidence rates.