Hypertension tied to poorer survival in tuberculosis
Tuberculosis (TB) patients with high blood pressure are at increased risk of death during the 9 months following initiation of TB treatment, a study has found. But the good news is that dihydropyridine calcium channel blockers (DHP-CCBs) may improve survival outcomes.
The study population comprised 2,894 adult patients (median age, 66.6 years; 68.2 percent male; median body mass index, 21.1 kg/m2) receiving treatment for culture-confirmed, drug-sensitive TB at the National Taiwan University Hospital. More than a third (36.4 percent) of these patients were hypertensive.
Hypertensive patients had higher rates of diabetes, cardiovascular diseases, cerebrovascular accidents, cancer and chronic kidney disease, among others. Meanwhile, normotensive patients were more likely to be smear-positive by microscopy (45.8 percent vs 37.4 percent) and have cavitary disease (16.6 percent vs 10.3 percent) at diagnosis.
Over a follow-up of 9 months, more patients in the hypertensive vs normotensive group died of any cause (29.1 percent vs 15.2 percent; p<0.001) and of infection-related causes (16.9 percent vs 8.1 percent; p<0.001).
Multivariable Cox proportional hazards analysis showed that hypertension contributed to increased mortality due to all causes (hazard ratio [HR], 1.57, 95 percent confidence interval [CI], 1.23–1.99) and infections (HR, 1.87, 95 percent CI, 1.34–2.6). Microbiological outcomes, on the other hand, did not significantly differ between the two groups.
Use of DHP-CCB conferred a protective benefit for all-cause mortality (HR, 0.67, 95 percent CI, 0.45–0.98) but only by univariate Cox regression. The drug was associated with neither infection-related mortality (HR, 0.78, 95 percent CI, 0.46–1.34) nor microbiological outcomes in univariate or multivariate regression analyses.
The study underscores the importance of screening for hypertension, especially in elderly patients newly diagnosed with TB.