Blood pressure trends and mortality

OBJECTIVE: To evaluate the independent contributions of both the trend in SBP and the SBP value at age 90 to the prediction of mortality in nonagenarians. METHODS: The trend in SBP between 85 and 90 years and SBP at age 90 years were assessed in a population-based sample of 271 participants (74 men and 197 women) aged 90 years of the Leiden 85-plus Study, an observational population-based prospective follow-up study (started 1997). Primary endpoint, followed up over 5 years (median 3.6 years), was all-cause mortality. RESULTS: A decreasing trend in SBP between 85 and 90 years (decline ≥2.9 mmHg/year) was associated with increased mortality compared to an average SBP trend (hazard ratio 1.45, 95% confidence interval 1.02-2.06), independent of SBP at age 90. The effect was stronger in institutionalized participants compared to those living independently hazard ratio 1.87 (1.10-3.19) and hazard ratio 1.30 (0.81-2.09). After analysis with a fully adjusted model, the estimate approached unity hazard ratio 1.08 (0.60-1.86). Overall, 90-year-old participants with SBP of 150 mmHg or less had a 1.62 times increased mortality risk compared to those with SBP more than 150 mmHg (1.21-2.20), independent of the SBP trend in preceding years. This applied to those with and without antihypertensive drugs and those with and without history of cardiovascular disease or noncardiovascular disease. In the fully adjusted model, the estimate was 1.47 (0.90-2.40). CONCLUSION: In very old age, both decreasing trend in SBP over the previous 5 years and the current SBP value independently contribute to prediction of all-cause mortality. Therefore, in individual patients, all available preceding SBP measurements should be taken into account.