Sleep duration, physical activity, and caloric intake are related to weight status in Mexican American children: a longitudinal analysis.

BACKGROUND: Obesity is a serious issue, spanning all ages, and, in the U.S., disproportionately affects Latinos and African Americans. Understanding sleep, physical activity and dietary behaviors that may predict childhood obesity can help identify behavioral intervention targets. METHODS: Data were drawn from a U.S. cohort study of 323 Mexican American 8-10-year-old children and their mothers, who participated in a longitudinal study over a 2-year period. Measures were collected at baseline (BL; child mean age = 8.87, SD = 0.83), year 1 (FU1) and year 2 (FU2). Mothers reported on household income and acculturation at BL. Child height and weight were collected and BMI z-scores (BMIz) were calculated for weight status at BL, FU1, and FU2. Accelerometer-estimated sleep duration (hours) and moderate-to-vigorous physical activity (MVPA; minutes) were collected across 3 days at BL, FU1, and FU2. Two 24-h dietary recalls were performed at each time point; from these, average energy intake (EI, kcals/day) was estimated. Cross-lagged panel analysis was used to examine behavioral predictors on BMIz at each time point and across time. RESULTS: At BL and FU1, longer sleep duration (ß = - 0.22, p < 0.001; ß = - 0.17, p < 0.05, respectively) and greater MVPA (ß = - 0.13, p < 0.05; ß = - 0.20, p < 0.01, respectively) were concurrently related to lower BMIz. At FU2, longer sleep duration (ß = - 0.18, p < 0.01) was concurrently related to lower BMIz, whereas greater EI (ß = 0.16, p < 0.01) was related to higher BMIz. Longer sleep duration at BL predicted lower BMIz at FU1 (ß = - 0.05, p < 0.01). CONCLUSIONS: Longer sleep duration was concurrently related to lower weight status at each time point from ages 8-10 to 10-12. Higher MVPA was concurrently related to lower weight status in earlier childhood (ages 8-10 and 9-11) and higher EI was concurrently related to higher weight status toward the end of childhood (ages 10-12 years). Furthermore, longer sleep in earlier childhood was protective of children's lower weight status 1 year later. These findings suggest that sleep duration plays a consistent and protective role against childhood obesity; in addition, MVPA and healthy EI remain important independent factors for obtaining a healthy weight.

Psychological stress and reproductive aging among pre-menopausal women.

BACKGROUND: Life history models suggest that biological preparation for current versus longer term reproduction is favored in environments of adversity. In this context, we present a model of reproductive aging in which environmental adversity is proposed to increase the number of growing follicles at the cost of hastening the depletion of the ovarian reserve over time. We evaluated this model by examining psychological stress in relation to reproductive aging indexed by antral follicle count (AFC), a marker of total ovarian reserve. We hypothesized that stress would be related to (i) higher AFC in younger women, reflecting greater reproductive readiness as well as (ii) greater AFC loss across women, reflecting more accelerated reproductive aging. METHODS: In a multi-ethnic, community sample of 979 participants [ages 25-45 (mean (standard deviation) = 35.2 (5.5)); 27.5% Caucasian] in the Ovarian Aging study, an investigation of the correlates of reproductive aging, the interaction of age-x-stress was assessed in relation to AFC to determine whether AFC and AFC loss varied across women experiencing differing levels of stress. Stress was assessed by the perceived stress scale and AFC was assessed by summing the total number of antral follicles visible by transvaginal ultrasound. RESULTS: In linear regression examining AFC as the dependent variable, covariates (race/ethnicity, socio-economic status, menarcheal age, hormone-containing medication for birth control, parity, cigarette smoking, bodymass index, waist-to-hip ratio) and age were entered on step 1, stress on step 2 and the interaction term (age-x-stress) on step 3. On step 3, significant main effects showed that older age was related to lower AFC (b = -0.882, P = 0.000) and greater stress was related to higher AFC (b = 0.545, P = 0.005). Follow-up analyses showed that the main effect of stress on AFC was present in the younger women only. A significant interaction term (b = -0.036, P = 0.031) showed the relationship between age and AFC varied as function of stress. When the sample was divided into tertiles of stress, the average follicle loss was -0.781, -0.842 and -0.994 follicles/year in the low-, mid- and high-stress groups, respectively. CONCLUSIONS: Psychological stress was related to higher AFC among younger women and greater AFC decline across women, suggesting that greater stress may enhance reproductive readiness in the short term at the cost of accelerating reproductive aging in the long term. Findings are preliminary, however, due to the cross-sectional nature of the current study.

Temporal associations between circadian sleep and activity patterns in Mexican American children.

OBJECTIVE: This study aimed to examine the relationship between circadian sleep and activity behaviors (sedentary time [SED], light-intensity physical activity [LPA], and moderate- to vigorous-intensity physical activity [MVPA]) across 3 consecutive days. METHODS: This study included 308 Mexican American children aged 8-10 years from the San Francisco Bay Area. Minutes of sleep duration, SED, LPA, and MVPA were estimated using hip-worn accelerometers from Wednesday night to Saturday night. A cross-lagged panel model was used to estimate paths between sleep duration the prior night and subsequent behaviors, and paths between behaviors to subsequent sleep duration across the 3 days. We adjusted for child age, sex, body mass index, and household income. RESULTS: Overall, children were 8.9 (SD 0.8) years old; the weighted average for weekday and weekend combined was 9.6 (SD 0.7) hours per night in sleep duration, 483 (SD 74) min/d SED, 288 (SD 61) min/d LPA, and 63 (SD 38) min/d MVPA. Cross-lagged panel analyses showed that, over 3 days, for every 1-hour increase in sleep duration, there were an expected 0.66-hour (40-minute) decrease in SED, 0.37-hour (22-minute) decrease in LPA, and 0.06-hour (4-minute) decrease in MVPA. For every 1-hour increase in LPA, there was an expected 0.25-hour (15-minute) decrease in sleep duration. CONCLUSION: An additional hour of sleep the night before corresponded to an hour decrease in combined SED and LPA the next day in Mexican American children. For every hour of LPA, there was an associated 15-minute decrease in sleep. Encouraging longer sleep may help to reduce SED and LPA, and help offset LPA's negative predictive effect on sleep.

Association of ethnicity, Fitzpatrick skin type, and hirsutism: A retrospective cross-sectional study of women with polycystic ovarian syndrome.

BACKGROUND: The complex interplay between ethnicity, Fitzpatrick skin type (FST), and hirsutism in patients with polycystic ovarian syndrome (PCOS) is poorly understood. OBJECTIVE: In this cross-sectional, retrospective analysis, we examined the prevalence, severity, and distribution of hirsutism with clinician-rated site-specific and total modified Ferriman-Gallwey (mFG) visual scoring in a diverse cohort of American patients with PCOS. METHODS: Independent analyses were conducted on the basis of patient-reported FST ratings and ethnicity. RESULTS: In this PCOS cohort, a correlation was found between hirsutism and ethnicity and the highest prevalence of hirsutism and total mFG scores was observed in Hispanic, Middle Eastern, African American, and South Asian patients. A positive correlation between hirsutism and FST was also observed with an increasing prevalence of hirsutism in the group of patients with higher FSTs. Significant trends in the anatomic distribution of hirsutism were observed between ethnic groups as well. A higher facial mFG score was found in African American patients but higher mFG scores in the truncal and extremity regions were observed in Middle Eastern patients. Truncal hirsutism was also associated with higher FSTs. CONCLUSIONS: Ethnicity and FST may be important variables in both the quantitative and qualitative presentations of hirsutism in women with PCOS and should be considered in the diagnostic evaluation of any patient who is suspected of having the condition. Previously published studies that examined ethnicity, FST, and hirsutism in homogeneous cohorts limited comparison and generalizability but the strength of this study lies in its detailed analysis within a single large and diverse PCOS cohort. Validated studies are needed to determine whether clinical criteria for hirsutism should be adjusted for ethnicity and FST in the PCOS population and particularly within diverse cohorts and patients of mixed ancestry.

Social support, conflict, and the development of marital dysfunction.

How spouses help each other contend with personal difficulties is an unexplored but potentially important domain for understanding how marital distress develops. Newly married couples participated in 2 interaction tasks: a problem-solving task in which spouses discussed a marital conflict and a social support task in which spouses discussed personal, nonmarital difficulties. Observational coding of these interactions showed that wives' support solicitation and provision behaviors predicted marital outcomes 2 years later, independent of negative behaviors during marital problem-solving discussions. In addition, couples who exhibited relatively poor skills in both behavioral domains were at particular risk for later marital dysfunction. These results suggest that social support exchanges should be incorporated into social learning analyses of marriage and into programs designed to prevent marital distress.