Effect of antitubercular medications on blood pressure control in chronic kidney disease patients with tuberculosis: a prospective cohort study.
BACKGROUND
Previous anecdotal reports suggested a decrease in antihypertensive medication potency after starting antitubercular medications. This interaction could be unpredictable in presence of renal failure due to increased half-lives of most commonly used antihypertensive medications.


METHODS
In a cohort study involving 135 patients with chronic kidney disease (CKD), 62 patients with tuberculosis star-ted on antitubercular medications (TB group) were prospectively compared with 73 CKD controls (with no TB and not on antitubercular medications) for a change in antihypertensive medications. Antihypertensive dose was converted to unit score.


RESULTS
The TB group had a greater increase in antihypertensive medication dose as compared with controls (89% vs. 54%, p<0.0001). In absolute terms an overall increase in antihypertensive medications was observed in 60% of pa-tients in the TB group, with a 2-fold dose increase from the baseline (p<0.0001). Four patients from the TB group de-veloped a hypertensive emergency. In multivariate linear regression, the association between TB group and increase in antihypertensives remained significant ( beta =0.38; p<0.0001).


CONCLUSIONS
In CKD patients, antihypertensive medication potency is reduced in TB patients on antitubercular the-rapy in a significant number of patients, to a clinically significant degree with a potential risk for hypertensive emergency.
Sharma
Ajay P
AP
Department of Pediatrics, University of Western Ontario, London, Ontario, Canada. ajay.sharma@lhsc.on.ca
Sural
Saubhik
S
Gupta
Amit
A
Garg
Amit X
AX
Gulati
Sanjeev
S
Sharma
Raj K
RK
D000328:Adult; D000959:Antihypertensive Agents / Q000008:administration & dosage* / Q000037:antagonists & inhibitors; D000995:Antitubercular Agents / Q000008:administration & dosage* / Q000037:antagonists & inhibitors; D001794:Blood Pressure / Q000187:drug effects*; D004336:Drug Antagonism; D005260:Female; D006801:Humans; D007676:Kidney Failure, Chronic / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D014376:Tuberculosis / Q000150:complications / Q000188:drug therapy* / Q000503:physiopathology
D000959:Antihypertensive Agents; D000995:Antitubercular Agents