J. D. Kark

OBJECTIVES: This study assessed the association of Jewish religious observance with mortality by comparing religious and secular kibbutzim. These collectives are highly similar in social structure and economic function and are cohesive and supportive communities. METHODS: In a 16-year (1970 through 1985) historical prospective study of mortality in 11 religious and 11 matched secular kibbutzim in Israel, 268 deaths occurred among 3900 men and women 35 years of age and older during 41347 person-years of observation. RESULTS: Mortality was considerably higher in secular kibbutzim. Cox proportional hazards analysis was used to adjust for age and the matched design; rate ratios were 1.67 (95% confidence interval [CI]=1.17, 2.39) for men, 2.67 (95% CI=1.55, 4.60) for women, and 1.93 (95% CI=1.44, 2.59) overall. Kaplan-Meier survival analysis of birth cohorts confirmed the association. The lower mortality in religious kibbutzim was consistent for all major causes of death. CONCLUSIONS: Belonging to a religious collective was associated with a strong protective effect not attributable to confounding by sociodemographic factors. Elucidation of mechanisms mediating this effect may provide etiologic insights and leads for intervention.

BACKGROUND: Leukocyte telomere length (LTL) is considered a biomarker of human aging and based on cross-sectional studies it shortens with age. However, longitudinal studies reported that many adults display LTL lengthening. METHODS: Using Southern blots, we compared cross-sectional rates of age-related LTL change across a ∼20 year age range with those based on longitudinal evaluations in three surveys (S1, S2, and S3) with three time intervals: S1-S2 (5.8 years), S2-S3 (6.6 years), and S1-S3 (12.4 years). Hierarchical linear modeling was used to explore LTL dynamics using LTL data from S1, S2, and S3. RESULTS: Cross-sectionally, mean LTL shortenings were 24.6, 25.4, and 23.6 bp/y at S1, S2, and S3, respectively. Longitudinally, more variation was observed in the rate of LTL change during the shorter than longer follow-up periods. Furthermore, using simple differences in LTL, 14.4% and 10.7% of individuals displayed LTL lengthening during S1-S2 and S2-S3, respectively, but only 1.5% during S1-S3 (p < 0.001). The estimated mean rate of LTL shortening based on averaging empirical Bayes' estimates of LTL from a parsimonious hierarchical linear modeling model was 31 bp/y with a range from 23 to 47 bp/y with none of the participants showing LTL lengthening over the average 12.4 years of follow-up. CONCLUSIONS: As aging displays a unidirectional progression, it is unlikely that LTL elongates with age. LTL elongation in longitudinal studies primarily reflects measurement errors of LTL in relation to the duration of follow-up periods.

A total community sample of 3,102 individuals from Evans County, Georgia, was followed for 12-14 years. During this period, 129 documented new cases of cancer were ascertained from medical records and death certificates. Cases were considered for inclusion only if documented at least 12 months after subjects were inducted into the cohort study. Cases were classified as definite, probable, and possible by strict criteria. Blood samples were drawn at the beginning of the study in 1960-62 and sera were frozen. Serum vitamin A (retinol) levels were measured in 1976 on the stored sera of 85 cancer patients and for 174 age-, race-, and sex-matched controls. Retinol estimations were performed by a fluorometric method after alumina column separation. Experiments conducted to simulate the exposure to light, thawing, and refreezing that sera may have undergone during the 14-16 years of storage showed retinol to be quite stable in response to these possible insults. As compared to controls, persons that eventually developed cancer had significantly lower mean serum retinol levels at least 12 months before the cancer diagnosis. The association was in the same direction for all 4 race-sex groups, although stronger overall for males than females, and was consistent for the various cancer sites and cell types. Both matched and regression residual analyses were used to control for the confounding variables considered: age, race, sex, obesity, social class, and smoking.

OBJECTIVE: The imminent deadline for the 1991 Persian Gulf War and, subsequently, the 18 missile attacks by Iraq on Israel represented an unusual, short-term, life-threatening stressor for an entire nation. We studied mortality in Israel in January and February 1991 to determine whether excess deaths were precipitated on days of missile attacks. DESIGN: A time-series mortality study. SETTING: The state of Israel. PARTICIPANTS: All Israelis aged 25 years and older. MAIN OUTCOME MEASURE: Daily mortality by sex, age, region, underlying cause, and place of death. RESULTS: On January 18, 1991, the day of the first strike on Israeli cities, a 58% increment in total mortality occurred in the Israeli population (95% confidence interval [CI], 34% to 86%; P < .0001), a 77% excess (95% CI, 40% to 120%) in women and a 41% excess (95% CI, 10% to 79%) in men. This excess mortality occurred largely in the targeted Tel Aviv-central coastal plain and Haifa regions from cardiovascular causes and mainly out of hospital, significantly more so (P < .01) in women than men. Subsequently, on 16 attack days no overall excess was noted, yet a 10% increase in out-of-hospital deaths occurred. CONCLUSIONS: Likely explanations for the initial increase in mortality include acute emotional stress coupled with breathing difficulties induced by gas masks and extended stay in sealed rooms with resultant hypoxia in susceptible individuals. Women were more vulnerable than men. The absence of elevated total mortality in the subsequent attacks suggests a rapid adaptation to the circumstances surrounding the war. The policy of an unventilated sealed room may have been detrimental.