Background: Nonsteroidal anti-inflammatory drug (NSAID) side effects can impair quality of life in patients with osteoarthritis. Due to its particular mechanism of action, paracetamol might bypass these negative effects.
Objectives: To determine both the role of paracetamol in the treatment of osteoarthritis patients and optimal combination of antihypertensives and antirheumatics for these patients.
Methods: A prospective clinical trial in a family practice included 110 treated hypertensives aged over 55 years: 50 controls and 60 also taking NSAIDs for osteoarthritis. This 3-month study compared two antihypertensives, lisinopril/hydrochlorothiazide fixed combination and amlodipine, with two NSAIDs, ibuprofen and piroxicam, and with paracetamol. Following clinical work-up and NSAID discontinuation for at least 3 days (run-in period of only 3-7 days), osteoarthritis subjects were randomized to 1-month periods of ibuprofen (400-600 mg t.i.d.) or piroxicam (10-20 mg o.d.) with one month of paracetamol (1000 mg t.i.d.) in the middle as a "wash-out" interval, continuing the prescribed amlodipine (5-10 mg o.d.) or lisinopril/hydrochlorothiazide fixed drug combination (10/6.25-20/12.5 mg o.d.), while control subjects (hypertensives with no osteoarthritis) were just keeping their antihypertensive therapy. Blood pressure was measured with standard mercury sphygmomanometer and with an automatic device, in standing, sitting and supine position. The intensity of arthritic pain (on a visual analogue scale from 1 to 10, where 0 means "no pain" and 10 "the worst pain you may imagine") and the patient's quality of life estimate (on a visual analogue scale from 1 to 10, where 0 means "general condition excellent" and 10 "the worst possible") were recorded.
Results: Blood pressure control was unchanged in the amiodipine group across the study periods and impaired in the lisinopril/ hydrochlorothiazide group during either ibuprofen or piroxicam, but not during paracetamol. In the amlodipine +/- ibuprofen subgroup, the reduction of the average pain intensity score throughout the study was significant (chi2 = 8.250; df 3; P = 0.037). In the lisinopril/hydrochlorothiazide +/- piroxicam subgroup, the assessed quality of life differed significantly (chi2 = 9.716; df 3; P = 0.018), while in the amlodipine +/- ibuprofen and amlodipine +/- piroxicam subgroups the changes were marginal (chi2 = 6.936; df 3; P = 0.072 and chi2 = 7146; df 3; P = 0.065, respectively).