Does leptin predict incident hypertension in older adults?

OBJECTIVE

Leptin is associated with blood pressure (BP) in experimental and cross-sectional studies, but only one previous prospective study of middle-aged men has reported the association between leptin and incident hypertension. We examined the association of leptin levels with incident hypertension in a population-based study of older men and women.

DESIGN

Longitudinal cohort study.

POPULATION

Participants were 602 community-dwelling older adults with normal baseline BP levels who attended a research clinic visit between 1984 and 1987 and again 4.4 years later (mean age was 66.2 +/- 11.4; 60.6% were men; mean body mass index (BMI) 24.9 +/- 3.4 kg/m(2)).

MEASUREMENTS

Hypertension was defined as systolic BP > or =140 mmHg and/or diastolic BP > or =90 mmHg and/or antihypertensive drug treatment. Leptin was measured by radioimmunoassay.

RESULTS

After an average 4.4-year follow-up (minimum 2-maximum 7 years), 106 (17.6%) new cases of hypertension were identified. At baseline, participants who developed hypertension were older and had higher systolic BP and higher total cholesterol compared to participants who remained normotensive. Baseline serum leptin levels were higher in participants who developed hypertension compared to persistent normotensives [median (25th-75th range)] [8.8(5-16) vs 7(4-11) ng/ml, P = 0.002]. In logistic regression models, leptin (log-transformed) predicted incident hypertension before and after adjustments for baseline age, BMI, systolic BP, total cholesterol, medications, and previous cardiovascular disease (OR 1.75 95% CI 1.17-2.61, P = 0.006). This association persisted after exclusion of 45 obese participants.

CONCLUSION

Higher leptin levels were independently associated with increased odds of incident hypertension in older adults.