(HealthDay News) — People who use combination nicotine replacement therapy (NRT) are more likely to successfully quit smoking than people who use a single form of NRT, according to a review published online in the Cochrane Database of Systematic Reviews.

Nicola Lindson, PhD, from the University of Oxford in the United Kingdom, and colleagues conducted a systematic literature review to identify studies evaluating the effectiveness and safety of different forms, deliveries, doses, durations, and schedules of NRT for achieving long-term smoking cessation.

The researchers identified 63 trials with 41,509 participants. They determined with high-certainty evidence that combination NRT (fast-acting form plus patch) results in higher long-term quit rates than the single form (relative risk [RR], 1.25; 95 percent confidence interval [CI], 1.15 to 1.36; based on 14 studies, 11,356 participants). Moderate-certainty evidence showed that patches with 42/44 mg are as effective as 21/22 mg (24-hour; RR, 1.09, 95 percent CI, 0.93 to 1.29; 5 studies, 1655 participants) and that 21-mg patches are more effective than 14-mg patches (24-hour; RR, 1.48; 95 percent CI, 1.06 to 2.08; one study, 537 participants). A benefit was noted for the higher-dose gum in 5 studies (4 mg versus 2 mg; RR 1.43; 95 percent CI, 1.12 to 1.83; 856 participants), although subgroup analysis suggests that only smokers who are highly dependent may benefit. Moderate-certainty evidence indicated a favorable effect of preloading (using NRT prior to quit day) on abstinence (RR, 1.25; 95 percent CI, 1.08 to 1.44; nine studies, 4,395 participants). Using either a form of fast-acting NRT or a nicotine patch results in similar long-term quit rates based on high-certainty evidence (RR, 0.9; 95 percent CI, 0.77 to 1.05; eight studies, 3,319 participants).

“This high-quality evidence clearly signposts that the most effective way to use NRT is to use a combination of 2 products at once, a patch and a fast-acting form such as gum, nasal spray, or lozenge,” Lindson said in a statement.

Two authors were involved in included trials of NRT preloading.

Reference

Lindson N, Chepkin SC, Ye W, Fanshawe TR, Bullen C, Hartmann‐Boyce J. Different doses, durations and modes of delivery of nicotine replacement therapy for smoking cessation. Coch Rev.