Fourteen studies (n=4,804 patients), including five RCTs and nine prospective controlled cohort studies, were included in the review. Jadad scores for the five RCTs ranged from 2 to 5, with two trials achieving maximum scores (5 points). The quality of the cohort studies was variable and most had methodological flaws.
Beta-blockers: Three RCTs (n=1,079) and five prospective cohort studies (n=658) evaluated beta-blockers. When pooled, the RCTs failed to find any significant difference between the intervention and control groups. However, the cohort studies showed a significant benefit in favour of beta-blockers (pooled growth rate difference -0.62mm/yr; 95% CI -1.00 to -0.24).
Antihypertensive agents: In the two cohort studies of other antihypertensive agents (four comparisons), all comparisons (except with diuretics) reported lower growth rates in the intervention groups in comparison with control. None of the differences were statistically significant. The studies were not pooled due to significant statistical heterogeneity.
Anti-inflammatory agents: Two RCTs of antibiotics (heterogeneity p=0.84), two cohort studies of statins (heterogeneity p<0.001) and one cohort study of non-steroidal anti-inflammatory drugs (NSAIDs) reported growth rates in favour of the intervention compared with the control group. In each case, the effects were generally larger than those reported for other types of interventions, but only the two pooled cohort studies of statins and one cohort study of NSAIDs showed a statistically significant difference in favour of the intervention.
No evidence of significant publication bias was found.