Association of Sustained Low or High Income and Income Changes With Risk of Incident Type 2 Diabetes Among Individuals Aged 30 to 64 Years

Importance

Evidence of the association between income fluctuation and risk of type 2 diabetes (T2D) is scarce.

Objective

To investigate whether sustained low or high income and income changes are associated with incidence of T2D.

Design, Setting, and Participants

In this population-based cohort study, more than 7.8 million adults without T2D aged 30 to 64 years from a nationally representative sample from the Korean Health Insurance Service database were enrolled in 2012 and followed up to 2019 (median follow-up, 6.3 years [IQR, 6.1-6.6 years]).

Exposures

Twenty quantiles of monthly health insurance premiums determined income levels. Income quartiles were annually analyzed from 2008 to 2012. Beneficiaries of the Medical Aid Program were regarded as those with very low income. A decrease in income was indicated as a reduction of 25% or more in income compared with income in the previous year.

Main Outcomes and Measures

The primary outcome was incident T2D based on the International Statistical Classification of Diseases and Related Health Problems, Tenth Revision codes E11 to E14, 1 or more claims of antidiabetic medication, or a fasting glucose level of 126 mg/dL or higher. Multivariable Cox proportional hazards models were used to assess the association of low- or high-income status and income changes with incidence of T2D.

Results

Of 7 821 227 participants (mean [SD] age, 46.4 [9.3] years; 54.9% men), 359 931 (4.6%) developed T2D at least 1 year after enrollment. Individuals who repeatedly experienced low and very low income for 5 years showed 22% (hazard ratio [HR], 1.22 [95% CI, 1.21-1.23]) and 57% (1.57 [95% CI, 1.53-1.62]) higher T2D risk compared with those who never experienced low and very low income, respectively. In contrast, individuals who were repeatedly in high-income quartiles showed lower T2D risk compared with those who never experienced high income (HR, 0.86 [95% CI, 0.85-0.86]). The number of income decreases was associated with elevated T2D risk (≥2 vs 0 income decreases: HR, 1.08 [95% CI, 1.06-1.11]; P < .001 for trend). When income quartile status was compared between 2008 and 2012, individuals who experienced an income increase had lowered T2D risk, while those who experienced an income decrease had elevated T2D risk in each income quartile group.

Conclusions and Relevance

This cohort study found that individuals who experienced sustained low-income status or an income decrease had elevated T2D risk, while those who had sustained high-income status or an income increase had lowered T2D risk.

Racial/Ethnic Disparities in the Relationship Between Traumatic Childhood Experiences and Suboptimal Sleep Dimensions Among Adult Women: Findings from the Sister Study

BACKGROUND

Traumatic childhood experiences (TCEs) are associated with poor adulthood sleep, but racial/ethnic disparities have not been well-studied. We investigated the TCE-adulthood sleep relationship among non-Hispanic (NH)-White, NH-Black, and Hispanic/Latina women.

METHOD

Women enrolled in the Sister Study from 2003 to 2009 reported the following TCEs in a follow-up interview (2008-2012): natural disasters; major accidents; household dysfunction; and sexual, physical, and psychological/emotional abuse. Sleep characteristics included short sleep duration (< 7 h vs. 7-9 h), long sleep onset latency (SOL) (> 30 vs. ≤ 30 min), frequent night awakenings (≥ 3 times/night ≥ 3 times/week [yes vs. no]), and frequent napping (≥ 3 vs. < 3 times/week). Using log-binomial regression to estimate prevalence ratios (PRs) and 95% confidence intervals (CIs) for sleep characteristics among women with vs. without TCEs, we investigated racial/ethnic-specific associations and race/ethnicity as a moderator.

RESULTS

Among 40,082 participants (mean age = 55 ± 8.8 years), 55% reported ≥ 1 TCE (NH-White, 54%; NH-Black, 62%; Hispanic/Latina, 57%). NH-White, NH-Black, and Hispanic/Latina women reporting any TCE had a higher prevalence of short sleep compared with their within-race/ethnicity counterparts without TCEs. Associations were strongest among NH-Whites. Compared to NH-Whites with no TCEs, racial/ethnic minorities who reported any TCEs had a higher prevalence of short sleep (PR_Blacks = 2.13 [95% CI 2.02-2.24], PR_{Hispanics/Latinas} = 1.47 [1.35-1.60]) and long SOL. When comparing racial/ethnic minorities with TCEs to NH-Whites with TCEs, PRs for short sleep (PR_Blacks = 1.98 [1.88-2.08] and PR_{Hispanics/Latinas} = 1.36 [1.25-1.48]) and long SOL were weaker.

CONCLUSION

TCEs were positively associated with poor sleep characteristics among women, and TCEs appear to contribute to short sleep duration and long SOL disparities.

Racial/ethnic disparities in sleep duration and sleep disturbances among pregnant and non-pregnant women in the United States

Sleep disturbances among pregnant women are increasingly linked to suboptimal maternal/birth outcomes. Few studies in the USA investigating sleep by pregnancy status have included racially/ethnically diverse populations, despite worsening disparities in adverse birth outcomes. Using a nationally representative sample of 71,644 (2,349 pregnant) women from the National Health Interview Survey (2004-2017), we investigated relationships between self-reported pregnancy and six sleep characteristics stratified by race/ethnicity. We also examined associations between race/ethnicity and sleep stratified by pregnancy status. We used average marginal predictions from fitted logistic regression models to estimate prevalence ratios (PRs) and 95% confidence intervals (CIs) for each sleep dimension, adjusting for sociodemographic and health characteristics. Pregnant women were less likely than non-pregnant women to report short sleep (PR_Overall  = 0.75; 95% CI, 0.68-0.82) and more likely to report long sleep (PR_Overall  = 2.06; 95% CI, 1.74-2.43) and trouble staying asleep (PR_Overall  = 1.34; 95% CI, 1.25-1.44). The association between pregnancy and sleep duration was less pronounced among women aged 35-49 years compared to those <35 years. Among white women, sleep medication use was less prevalent among pregnant compared to non-pregnant women (PR_White  = 0.45; 95% CI, 0.31-0.64), but this association was not observed among black women (PR_Black  = 0.98; 95% CI, 0.46-2.09) and was less pronounced among Hispanic/Latina women (PR_{Hispanic/Latina}  = 0.82; 95% CI, 0.38-1.77). Compared to pregnant white women, pregnant black women had a higher short sleep prevalence (PR_Black  = 1.35; 95% CI, 1.08-1.67). Given disparities in maternal/birth outcomes and sleep, expectant mothers (particularly racial/ethnic minorities) may need screening followed by treatment for sleep disturbances. Our findings should be interpreted in the historical and sociocultural context of the USA.

Multiple sleep dimensions and type 2 diabetes risk among women in the Sister Study: differences by race/ethnicity

Objective

Poor sleep has been associated with type 2 diabetes. Since racial/ethnic minorities experience a disproportionately high prevalence of poor sleep and type 2 diabetes, we sought to determine the relationships between multiple sleep dimensions and incident type 2 diabetes and to investigate if these relationships vary by race/ethnicity.

Research design and methods

Prospective data were analyzed from the Sister Study, which enrolled 50 884 women from 2003 to 2009. Participants self-reported sleep duration, sleep latency, night awakenings, and napping at baseline, and a physician's diagnosis of type 2 diabetes at follow-up. Multivariable-adjusted HRs and 95% CIs were estimated using Cox proportional hazards models.

Results

Among the 39 071 eligible participants, 87% self-identified as white, 8% black and 5% Hispanic/Latina. The mean follow-up period was 8.5±2.1 years and 1785 type 2 diabetes cases were reported. The incidence rate per 1000 person-years was 5.4 for whites, 13.3 for blacks and 11.6 for Hispanics/Latinas. There was a positive but non-significant increased risk of type 2 diabetes among women who reported short sleep, latency >30 min and frequent night awakenings. In fully-adjusted models, frequent napping was associated with a 19% (HR 1.19, 95% CI 1.04 to 1.37) higher type 2 diabetes risk in the overall sample. Poor sleep among racial/ethnic minorities ranged from a 1.4-fold to a 3.2-fold higher type 2 diabetes risk than whites with recommended sleep.

Conclusions

Frequent napping was associated with higher type 2 diabetes risk. Racial/ethnic minorities with poor sleep had a higher type 2 diabetes risk than whites with recommended sleep.

Traumatic childhood experiences and multiple dimensions of poor sleep among adult women

STUDY OBJECTIVES

Exposure to traumatic childhood experiences (TCEs) may contribute to poor sleep in adulthood. Previous studies have been limited to mainly investigating physical and sexual abuse and did not consider betrayal trauma, or whether the victim regarded the perpetrator as someone socially close to them, the age group at occurrence, and trauma-related distress/anxiety.

METHODS

We used a large cohort of US women, 35-74 years old, enrolled in the Sister Study from 2003 to 2009. Self-reports of specific TCEs occurring before the age of 18 years included sexual, physical, and psychological/emotional trauma; natural disasters; major accidents; and household dysfunction. Participants self-reported average sleep duration (short: <7 hours vs recommended: 7-9 hours), sleep onset latency (SOL) at least 30 vs less than 30 minutes, at least 3 night awakenings once asleep at least 3 times/week (Night awakenings [NA], yes vs no), and napping at least 3 vs less than 3 times/week.

RESULTS

Among 40 082 women, 55% reported a TCE, with 82% reporting betrayal trauma. Compared to women reporting no TCE, women with any TCE were more likely to report short sleep (prevalence ratio [PR] = 1.08, [95% confidence interval (CI) = 1.04 to 1.11]), longer SOL (1.11, [1.06 to 1.16]), frequent NAs (1.06, [1.00 to 1.11]), and frequent napping (1.05, [0.99 to 1.12]). The relationship between experiencing any TCE and short sleep was stronger for TCEs by a perpetrator considered socially close vs not close (1.12, [1.09 to 1.16]), SOL (1.27, [1.22 to 1.33]), NA (1.20, [1.14 to 1.27]), and napping (1.24, [1.17 to 1.32]).

CONCLUSIONS

TCEs were associated with poor sleep in women with greater impact when the perpetrator was regarded as close. More research is warranted to better understand pathways between childhood trauma and sleep health in adulthood to develop effective interventions.

Multiple poor sleep characteristics and metabolic abnormalities consistent with metabolic syndrome among white, black, and Hispanic/Latina women: modification by menopausal status

BACKGROUND

Poor sleep is a potential risk factor for metabolic syndrome (MetS), and its relationship with MetS may vary by race/ethnicity and menopausal status among women.

METHODS

We used Sister Study enrollment data from 2003 to 2009 to investigate the cross-sectional associations between multiple subjective sleep characteristics and having ≥ 3 prevalent metabolic abnormalities consistent with MetS among white, black, and Hispanic/Latina women. Self-reported sleep characteristics included average sleep duration (short [< 7 h] vs. recommended [7-9 h]), sleep debt (≥ 2-h difference between shortest and longest sleep duration, napping ≥ 3 times/week, and insomnia symptoms (difficulty falling or staying asleep). We used Poisson regression with robust variance to estimate adjusted prevalence ratios (PRs) and 95% confidence intervals (CIs) to compare MetS prevalence between women with poor sleep (e.g., short sleep, sleep debt, frequent napping, or insomnia symptoms [all yes vs. no]) and non-poor sleep within menopausal status categories (premenopausal or postmenopausal). We adjusted for sociodemographic characteristics, mental health, and health behaviors.

RESULTS

Among 38,007 eligible women (13,988 premenopausal, 24,019 postmenopausal), mean age was 55 ± 8.8 years, racial/ethnic composition was 86.63% white, 8.53% black, and 4.84% Hispanic/Latina, and 12% had MetS. Associations between certain poor sleep characteristics [i.e., short sleep (PRpremenopausal = 1.23 [95% CI 1.06-1.42], PRpostmenopausal = 1.09 [1.02-1.16], pshort sleep*menopause = 0.0070) and insomnia symptoms (PRpremenopausal = 1.21 [1.05-1.41], PRpostmenopausal = 1.11 [1.05-1.18], pinsomnia symptoms*menopause = 0.035)] and prevalent MetS were stronger among premenopausal compared to postmenopausal women, but did not vary by race/ethnicity. Associations between concurrent short sleep/insomnia symptoms and MetS were stronger among white and Hispanic/Latina postmenopausal women compared to their black counterparts. Menopausal status and race/ethnicity did not modify positive associations for other poor sleep characteristics.

CONCLUSIONS

Poor sleep was positively associated with MetS prevalence. Associations between individual poor sleep characteristics (i.e., short sleep, insomnia symptoms) were stronger among premenopausal compared to postmenopausal women but did not vary by race/ethnicity.

Impact of gestational weight gain and prepregnancy body mass index on the prevalence of large-for-gestational age infants in two cohorts of women with type 1 insulin-dependent diabetes: a cross-sectional population study

OBJECTIVES

Despite improvements in treatment modalities, large-for-gestational age (LGA) prevalence has remained between 30% and 40% among infants of mothers with type 1 insulin-dependent diabetes mellitus (TIDM). Our objective was to estimate LGA prevalence and examine the association between gestational weight gain (GWG) and prepregnancy body mass index (BMI) with LGA among mothers with TIDM.

DESIGN

Cross-sectional study.

SETTING

Regional data in Cincinnati, Ohio, from the Diabetes in Pregnancy Program Project (PPG), a prospective cohort for the period 1978-1993; national data from Consortium on Safe Labor (CSL), a multicentre cross-sectional study for the period 2002-2008.

PARTICIPANTS

The study included 333 pregnancies in the PPG and 358 pregnancies in the CSL. Pregnancies delivered prior to 23 weeks' gestation were excluded. Women with TIDM in the PPG were identified according to physician confirmation of ketoacidosis, and/or c-peptide levels, and by International Classification of Diseases, ninth version codes within the CSL. LGA was identified as birth weight >90th percentile according to gestational age, race and sex.

MAIN OUTCOME MEASURES

LGA at birth.

RESULTS

Mean±SD maternal age at delivery was 26.4±5.1 years for PPG women and 27.5±6.0 years for CSL women, p=0.008. LGA prevalence did not significantly differ between cohorts (PPG: 40.2% vs CSL: 36.6%, p=0.32). More women began pregnancy as overweight in the later cohort (PPG (16.8%) vs CSL (27.1%), p<0.001). GWG exceeding Institute of Medicine (IOM) guidelines was higher in the later CSL (56.2%) vs PPG (42.3%) cohort, p<0.001. Normal-weight women with GWG within IOM guidelines had a lower LGA prevalence in CSL (PPG: 30.6% vs CSL: 13.7%), p=0.001.

CONCLUSIONS

Normal-weight women with GWG within IOM guidelines experienced a lower LGA prevalence, supporting the importance of adherence to IOM guidelines for GWG to reduce LGA. High BMI and GWG may be hindering a reduction in LGA prevalence.

Assessing the Impact of Excessive Gestational Weight Gain Among Women With Type 1 Diabetes on Overweight/Obesity in Their Adolescent and Young Adult Offspring: A Pilot Study

Aims/hypothesis: We sought to determine the impact of intrauterine exposure to excessive gestational weight gain (GWG) on overweight/obesity in adolescent/young adult offspring of women with type 1 diabetes mellitus (TIDM). Methods: In 2008, a pilot study was conducted among 19 randomly-selected adolescent and adult offspring of mothers with TIDM who participated in the Diabetes in Pregnancy Program Project (DiP) between 1978 and 1995. Body mass index (BMI)-specific Institute of Medicine (IOM) guidelines for gestational weight gain (GWG) were defined as: 12.5-18.0 kilograms (kg) GWG; 11.5-16.0 kg GWG: 7.0-11.5 kg GWG; 5.0-9.0 kg GWG, for women classed as underweight, normal, overweight and obese according to pre-pregnancy BMI, respectively. Generalized estimating equations were used to estimate adjusted odds ratios (aOR, [95% confidence intervals, CI]) for overweight/obesity among offspring, related to IOM adherence, adjusting for pre-pregnancy BMI and mean maternal daily insulin units/kg body weight. Results: Mean age of offspring at follow-up was 20.3 ± 3.3 years, 12(63%) were male, 4(21%) Black and 12(63%) overweight/obese. There were 9(82%) overweight/obese offspring among the 11 mothers who exceeded IOM guidelines for GWG compared with 3(38%) overweight/obese offspring among the 8 mothers with GWG within guidelines. Exceeding vs. adhering to IOM guidelines (OR = 7.50, [95%CI: 0.92-61.0]) and GWG per kilogram (OR = 1.39, [95%CI: 0.98-1.97]) were associated with offspring overweight/obesity at follow-up. Conclusions/interpretation: Our pilot study suggests potential long-term implications of excessive GWG on metabolic health in offspring of mothers with TIDM, warranting future research examining the health impact of GWG in this population.