Liver function tests and mortality in a cohort of life insurance applicants.

Since the widespread introduction of the blood test requirement for life insurance, the interpretation of liver function tests (AST, ALT, GGT) has generated intense interest. Elevated aspartate aminotransferase (AST) and alanine aminotransferase (ALT) have been shown to be associated with primary liver diseases, as well as increased all-cause mortality. Much of this mortality is mediated by increased cardiovascular risk. Gamma-glutmyltransferase (GGT) has been shown to be a marker for metabolic syndrome and diabetes, cardiovascular diseases and mortality, chronic kidney disease, as well as cancer incidence, and liver disease. In this paper we present a mortality study of abnormal liver function test (LFT) results using a direct life insurer's underwriting application data covering approximately 560,000 applications with insurance blood profiles. The results show a consistent progression of increasing risk ratios as the severity of the LFT finding increases. When GGT alone is elevated or when both ALT and AST are elevated, mortality risk is significantly elevated. Similarly, a trend toward higher mortality with progressively higher levels of ALT, AST and GGT is demonstrated. Related liver chemistry results (alkaline phosphatase, bilirubin, albumin), other risk factors, and age are also considered.

Comparison of body mass index and waist circumference as predictors of all-cause mortality in a male insured lives population.

Obesity assessed by body mass index (BMI) is associated with increased mortality risk, but there is uncertainty about whether BMI is the best way to measure obesity. Waist circumference (WC) has been proposed as a better measure. The Swiss Re BMI/WC Study was conducted to determine whether BMI or WC is a better predictor of future all-cause mortality in a large male insurance population. Using Cox proportional hazard models, risk ratios for increasing BMI and WC were 1.033 (P < .001) and 1.027 (P < .001), respectively. Risk ratios for obesity defined by BMI > or = 30 kg/m2 and WC > or = 40 inches were 1.33 (P < .001) and 1.20 (P = .002), respectively. In this study, BMI and WC are essentially equivalent in their ability to predict mortality risk in a male insurance population. Obesity, measured by either BMI or WC, has important underwriting and pricing implications.

Relationships between treated hypertension and subsequent mortality in an insured population.

OBJECTIVE: To investigate if a mortality differential exists between insurance policyholders with treated hypertension and policyholders who are not under such treatment, where both groups are noted to have the same blood pressure at the time of policy issue. BACKGROUND: Hypertension is a known mortality risk factor in the insured and general population. Treatment for hypertension is very common in the insured population, especially as age increases. At the time of insurance application, a subset of individuals with treated hypertension will have blood pressures that are effectively controlled and are in the normal range. These individuals often meet established preferred underwriting criteria for blood pressure. In some life insurance companies, they may be offered insurance at the same rates as individuals who are not hypertensive with the same blood pressure. Such companies make the assumption that the pharmacologically induced normotensive state confers no excess risk relative to the natural normotensive state. Given the potential pricing implications of this decision, we undertook an investigation to test this hypothesis. METHODS: We studied internal data on direct and reinsurance business between 1975 and 2001 followed through anniversaries in 2002 or prior termination with an average duration of 5.2 years per policy. Actual-to-expected analyses and Cox proportional hazards models were used to assess if a mortality differential existed between policyholders coded for hypertension and policyholders with the same blood pressure that were not coded as hypertensive. RESULTS: Eight thousand six hundred forty-seven deaths were observed during follow-up in the standard or preferred policy cohort. Within the same blood pressure category, mortality was higher in policyholders identified as treated hypertensives compared with those in the subset of individuals who were not coded for hypertension. This finding was present in males and females and persisted across age groups in almost all age-gender-smoking status subsets examined. The differential in mortality was 125% to 160% of standard mortality based on the ratio of actual-to-expected claims. CONCLUSION: In this insured cohort, a designation of treated hypertension is associated with increased relative mortality compared to life insurance policyholders not so coded.

Relationships between serum lipids and subsequent mortality in an insured population.

OBJECTIVES: To investigate relationships between serum lipids and all-cause mortality in an insured population issued policies at standard rates using contemporary analytic techniques. BACKGROUND: As with other preferred risk factors, differences in lipid profiles can be an important contributor to morbidity and mortality endpoints in the general and insured population. To better understand the independent contribution of different lipid profiles to mortality, contemporary researchers commonly employ multivariate statistical techniques. Studies on insured populations utilizing multivariate statistical procedures are not commonly published and are employed in this study of an insured cohort. METHODS: We studied internal data on direct and reinsurance business issued at standard rates, or rated only for abnormal lipids, between 1975 and 2000 followed through anniversaries in 2001, or prior termination, with an average duration of 6 years per policy. Cox proportional hazards models were used to study the multivariate relationship between various lipid values (cholesterol, cholesterol/HDL ratio, triglycerides) and mortality. RESULTS: Five hundred twenty deaths were observed during follow-up. Mortality was noted to vary by differing levels of all 3 of the predictor variables of interest. The relationship between an abnormal lipid profile and mortality was strongest in males and nonsmokers. CONCLUSIONS: In this insured cohort, changes in lipid profiles are associated with significant differentials in mortality.

Consequences of low dietary magnesium and high dietary calcium on pregnancy outcome and tissue mineralization in rats.

Weanling female Sprague-Dawley rats were fed purified diets to determine the influence of excess dietary calcium upon tissue content of magnesium and calcium, and reproductive outcome. Two levels of calcium (5000 and 16,000 ppm) and magnesium (200 and 1200 ppm) in a 2x2 factorial design (adequate magnesium and calcium = C; low magnesium adequate calcium = L; high calcium adequate magnesium = CHC; and high calcium low magnesium = LHC) were used during the study which included growth and breeding (10 weeks), and gestation and lactation (6 weeks). Depressed weight gain during growth and gestation occurred in response to calcium excess. Renal calcium accumulation was reduced in LHC dams as compared to L dams. In dams fed excess calcium, magnesium concentrations of bone, serum, and kidney were depressed while serum alkaline phosphatase activity increased. The adverse effects of high calcium seen in the dams were not apparent in LHC pups. These pups were heavier and more viable during lactation than pups in the L group. High dietary calcium in combination with low dietary magnesium during one reproductive cycle resulted in altered mineral levels in tissues and improved growth and viability of pups when compared to magnesium-deficient animals.