Back and neck pain : Epidemiological studies on some risk factors and treatments, including naprapathic manual therapy

Introduction: Back and neck pain are common and constitute the main cause for persistent pain in the population. The knowledge about the etiology and about the effect of different treatments that are offered for back and neck pain is not fully understood, with a few exceptions. Objectives: The overall aim of this thesis was to give epidemiological aspects of some potential risk factors for back and neck pain, as well as on manual treatment of such pain. Objectives in Studies I and II were to expand the knowledge about life events and coping style, and how they affect the risk of low back and/or neck/shoulder pain. In Study III, the objective was to investigate how smoking and alcohol consumption, respectively, affect the risk of long-term sick leave due to back or neck pain. The objective in Study IV was to evaluate the effects of the in Scandinavia commonly occurring naprapathic manual therapy for patients with nonspecific pain in the back and/or neck. Materials and Methods: Studies I and II are based on the population-based MUSICNorrtalje case-control study that comprised men and women 20-59-years-old, living in and not working outside a municipality in Sweden. Cases (n=1,148) were subjects from the study base who sought care for a new episode of low back and/or neck/shoulder pain during the study period 1993-1997. Controls (n=1,700) were selected as a stratified random sample from the study base with consideration taken for sex and age. Life events and critical life changes were measured by semistructured interviews, and the coping style was measured with a questionnaire. Study III is based on the HAKuL-Study, a three-year prospective cohort study. New periods of sick leave (> 28 days) due to back and/or neck pain were consecutively reported during three years from baseline, among 6,532 persons that in questionnaires at baseline had reported on their smoking and alcohol habits. Study IV is based on the BJORN-Trial, a randomized controlled trial with 409 patients with non-specific back and neck pain. The interventions compared were naprapathy, including spinal manipulation/mobilization, massage and stretching (Index Group), and support and advice on staying active and on pain coping strategies, according to the best scientific evidence available, provided by a physician (Control Group). Questionnaires were mailed to all participants after 3, 7 and 12 weeks, and the two groups were compared using the “intention to treat” principle. Results and conclusions: Having experienced at least two life events or critical life changes during the preceding five years was associated with an increased risk of neck/shoulder pain. A covert coping style was more common among women and was associated with an increased risk of neck/shoulder pain among women, but not among men. In general, no associations were observed in relation to the risk of low back pain. An interaction effect between a covert coping style and psychosocial stress was observed among women (Studies I and II). Regarding the risk of long-term sick leave due to back and neck pain, smoking involved an increased risk, whereas alcohol consumption tended to involve a decreased risk (Study III). Naprapathic manual treatment were statistically and clinically significant more effective than evidencebased advice on staying active and on pain coping strategies for non-specific back and neck pain, after 7 and 12 weeks (Study IV).