Symptoms and Engagement in Anti-social Behavior 10 Years After Mild Traumatic Brain Injury Within a Community Civilian Sample: A Prospective Cohort Study With Age-Sex Matched Control Group.

OBJECTIVE: To determine if there are longer-term effects on symptoms, health status, mood, and behavior 10 years after a mild traumatic brain injury (mTBI). DESIGN: Prospective cohort study. SETTING: Community-based, civilian sample. PARTICIPANTS: Adults aged ≥16 years at follow-up who experienced an mTBI 10 years ago, and an age and sex-matched non-injured control group. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: mTBI cases and controls were asked to complete self-report assessments of functioning (WHO Disability Assessment Schedule Version 2), symptoms (Rivermead Post-Concussion Symptom Questionnaire), health status (100-point scale), alcohol (Alcohol Use Disorders Identification Test) and substance use (Alcohol, Smoking and Substance Involvement Screening Test), and whether they had engaged in any anti-social behaviors over the past 12 months. RESULTS: Data were analyzed for 368 participants (184 mTBI cases and 184 age-sex matched controls). Just over a third of mTBI cases (64, 34.8%) reported that they were still affected by their index mTBI 10 years later. After adjusting for education and ethnicity, the mTBI group had statistically higher overall symptom burden (F=22.32, P<.001, ηp2=0.07) compared with controls. This difference remained after excluding those who experienced a recurrent TBI. The mTBI group were more than 3 times as likely to have engaged in anti-social behavior during the previous 12 months (F=5.89, P=.02). There were no group differences in health status, functioning, or problematic alcohol or substance use 10 years post-injury. CONCLUSIONS: This study provides evidence of potential longer-term associations between mTBI, post-concussion symptoms, and anti-social behavior which warrants further evaluation. Future research should also examine if longer-term effects may be preventable with access to early rehabilitation post-injury.

Brain Injury Screening Tool (BIST): test-retest reliability in a community adult sample.

OBJECTIVE: To determine the test-retest reliability of the Brain Injury Screening Tool (BIST), which was designed to support the initial assessment of mild traumatic brain injury (mTBI) across a variety of contexts, including primary and secondary care. DESIGN: Test-retest design over a 2-week period. SETTING: Community based. PARTICIPANTS: Sixty-eight adults (aged 18-58 years) who had not experienced an mTBI within the last 5 years and completed the BIST on two different occasions. MEASURES: Participants were invited to complete the 15-item BIST symptom scale and the Depression, Anxiety and Stress Scale (DASS-21) online at two time-points (baseline and 2 weeks later). To account for large variations in mood affecting symptom reporting, change scores on the subscales of the DASS-21 were calculated, and outliers were removed from the analysis. RESULTS: The BIST total symptom score and subscale scores (physical-emotional, cognitive and vestibular) demonstrated moderate to good test-retest reliability with intraclass correlation coefficients ranging between 0.51 and 0.83. There were no meaningful differences between symptom reporting on the total scale or subscales of the BIST between time1 and time2 at the p<0.05 level when calculated using related samples Wilcoxon signed-rank tests. CONCLUSION: The BIST showed evidence of good stability of symptom reporting within a non-injured, community adult sample. This increases confidence that changes observed in symptom reporting in an injured sample are related to actual symptom change rather than measurement error and supports the use of the symptom scale to monitor recovery over time. Further research is needed to explore reliability of the BIST within those aged <16 years.

NZ-RugbyHealth Study: Self-reported Injury Experience and Current Health of Former Rugby Union and Non-contact Sport Players.

BACKGROUND: There is limited research on associations between playing rugby union and player health post-retirement. OBJECTIVE: This study investigated differences in self-reported sport injury history and current self-reported health characteristics between former New Zealand rugby and non-contact sport players with a view to identifying issues to be further investigated with stronger epidemiological research designs. METHODS: Using a cross-sectional design, the NZ-RugbyHealth study surveyed 470 former rugby and non-contact sport players (43.8 ± 8.1 years; 127 elite rugby, 271 community rugby, 72 non-contact sport) recruited from October 2012 to April 2014. Demographic information, engagement in sport, sport injuries, medical conditions, mood, alcohol and substance use and ratings of current health status were obtained from a self-report 58-item general health e-questionnaire. We highlighted standardised differences in means of > 0.6 and differences in relative percentages of > 1.43 for variables between groups as representing at least moderate effect sizes, and of being worthy of follow-up studies. RESULTS: Higher percentages of the elite rugby player group had sustained injuries of a given body-site type (e.g. neck sprain/strain, thigh bruising, hamstring strain) combination than the non-contact sports players. Higher percentages of the rugby groups reported having sustained concussion (94% for elite, 82% for community, 26% for non-contact), injuries requiring hospitalisation (73%, 46%, 25%), injuries that stopped participation in sport permanently (28%, 28%, 11%) and sport-related surgery (72%, 46%, 32%) during their playing career. Both rugby groups had a higher prevalence of osteoarthritis (37%, 18%, 6%) than non-contact athletes and community rugby players had higher levels of hazardous alcohol consumption (38%, 40%, 25%) in retirement than non-contact athletes. There was little difference between rugby players and non-contact sports athletes in self-reported mood, substance use and current physical or psychological health ratings. CONCLUSIONS: Former rugby player groups were at higher risk than the non-contact player group for most injuries during their playing careers, and in retirement had greater prevalence of osteoarthritis and hazardous alcohol consumption. The relative youth of the groups (43.8 years on average) means that health issues that typically do not emerge until later life may not have yet manifested.

Rasch analysis of the Brain Injury Screening Tool (BIST) in mild traumatic brain injury.

OBJECTIVE: To evaluate the psychometric properties of the Brain Injury Screening Tool (BIST) symptom scale in a sample of people with a mild Traumatic Brain Injury (mTBI) through Rasch analysis, and to obtain an interval level measurement score for potential clinical use. MATERIALS AND METHODS: Data were obtained from 114 adults aged over 16 years, who had experienced at least one mTBI in the past 10 years. Participants were recruited via social media, concussion clinics and sports organisations over a 4-month period between May and September 2020. Participants were asked to compete the symptom scale of the BIST tool via an anonymous online questionnaire. Internal construct validity, dimensionality, person separation index, and differential item functioning of the BIST were examined with Rasch analysis. RESULTS: BIST in its original form produced a satisfactory item-trait interaction, and good reliability, but was found to be multi-dimensional. Rasch analysis of the full scale with three domains as subtests resulted in acceptable model fit (χ2(6) =3.8, p >  0.05), with good reliability (Person Separation Index = 0.84), and uni-dimensionality. Differential Item Functioning (DIF) analysis displayed no significant DIF effects for sex or age revealing that people responded consistently and similarly to the individual BIST items based on severity of symptom burden. CONCLUSIONS: The 15-item symptom scale of the BIST tool is a psychometrically sound measure of symptom burden following mTBI. The findings provide support for use of both total and sub scale scores for clinical use. Ordinal to interval score conversions are recommended for use when using the scores for research purposes in mTBI.

30-Year Trends in Stroke Rates and Outcome in Auckland, New Zealand (1981-2012): A Multi-Ethnic Population-Based Series of Studies.

BACKGROUND: Insufficient data exist on population-based trends in morbidity and mortality to determine the success of prevention strategies and improvements in health care delivery in stroke. The aim of this study was to determine trends in incidence and outcome (1-year mortality, 28-day case-fatality) in relation to management and risk factors for stroke in the multi-ethnic population of Auckland, New Zealand (NZ) over 30-years. METHODS: Four stroke incidence population-based register studies were undertaken in adult residents (aged ≥15 years) of Auckland NZ in 1981-1982, 1991-1992, 2002-2003 and 2011-2012. All used standard World Health Organization (WHO) diagnostic criteria and multiple overlapping sources of case-ascertainment for hospitalised and non-hospitalised, fatal and non-fatal, new stroke events. Ethnicity was consistently self-identified into four major groups. Crude and age-adjusted (WHO world population standard) annual incidence and mortality with corresponding 95% confidence intervals (CI) were calculated per 100,000 people, assuming a Poisson distribution. RESULTS: 5400 new stroke patients were registered in four 12 month recruitment phases over the 30-year study period; 79% were NZ/European, 6% Maori, 8% Pacific people, and 7% were of Asian or other origin. Overall stroke incidence and 1-year mortality decreased by 23% (95% CI 5%-31%) and 62% (95% CI 36%-86%), respectively, from 1981 to 2012. Whilst stroke incidence and mortality declined across all groups in NZ from 1991, Maori and Pacific groups had the slowest rate of decline and continue to experience stroke at a significantly younger age (mean ages 60 and 62 years, respectively) compared with NZ/Europeans (mean age 75 years). There was also a decline in 28-day stroke case fatality (overall by 14%, 95% CI 11%-17%) across all ethnic groups from 1981 to 2012. However, there were significant increases in the frequencies of pre-morbid hypertension, myocardial infarction, and diabetes mellitus, but a reduction in frequency of current smoking among stroke patients. CONCLUSIONS: In this unique temporal series of studies spanning 30 years, stroke incidence, early case-fatality and 1-year mortality have declined, but ethnic disparities in risk and outcome for stroke persisted suggesting that primary stroke prevention remains crucial to reducing the burden of this disease.

Mind and body therapy for fibromyalgia.

BACKGROUND: Mind-body interventions are based on the holistic principle that mind, body and behaviour are all interconnected. Mind-body interventions incorporate strategies that are thought to improve psychological and physical well-being, aim to allow patients to take an active role in their treatment, and promote people's ability to cope. Mind-body interventions are widely used by people with fibromyalgia to help manage their symptoms and improve well-being. Examples of mind-body therapies include psychological therapies, biofeedback, mindfulness, movement therapies and relaxation strategies. OBJECTIVES: To review the benefits and harms of mind-body therapies in comparison to standard care and attention placebo control groups for adults with fibromyalgia, post-intervention and at three and six month follow-up. SEARCH METHODS: Electronic searches of the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE (Ovid), EMBASE (Ovid), PsycINFO (Ovid), AMED (EBSCO) and CINAHL (Ovid) were conducted up to 30 October 2013. Searches of reference lists were conducted and authors in the field were contacted to identify additional relevant articles. SELECTION CRITERIA: All relevant randomised controlled trials (RCTs) of mind-body interventions for adults with fibromyalgia were included. DATA COLLECTION AND ANALYSIS: Two authors independently selected studies, extracted the data and assessed trials for low, unclear or high risk of bias. Any discrepancy was resolved through discussion and consensus. Continuous outcomes were analysed using mean difference (MD) where the same outcome measure and scoring method was used and standardised mean difference (SMD) where different outcome measures were used. For binary data standard estimation of the risk ratio (RR) and its 95% confidence interval (CI) was used. MAIN RESULTS: Seventy-four papers describing 61 trials were identified, with 4234 predominantly female participants. The nature of fibromyalgia varied from mild to severe across the study populations. Twenty-six studies were classified as having a low risk of bias for all domains assessed. The findings of mind-body therapies compared with usual care were prioritised.There is low quality evidence that in comparison to usual care controls psychological therapies have favourable effects on physical functioning (SMD -0.4, 95% CI -0.6 to -0.3, -7.5% absolute change, 2 point shift on a 0 to 100 scale), pain (SMD -0.3, 95% CI -0.5 to -0.2, -3.5% absolute change, 2 point shift on a 0 to 100 scale) and mood (SMD -0.5, 95% CI -0.6 to -0.3, -4.8% absolute change, 3 point shift on a 20 to 80 scale). There is very low quality evidence of more withdrawals in the psychological therapy group in comparison to usual care controls (RR 1.38, 95% CI 1.12 to 1.69, 6% absolute risk difference). There is lack of evidence of a difference between the number of adverse events in the psychological therapy and control groups (RR 0.38, 95% CI 0.06 to 2.50, 4% absolute risk difference).There was very low quality evidence that biofeedback in comparison to usual care controls had an effect on physical functioning (SMD -0.1, 95% CI -0.4 to 0.3, -1.2% absolute change, 1 point shift on a 0 to 100 scale), pain (SMD -2.6, 95% CI -91.3 to 86.1, -2.6% absolute change) and mood (SMD 0.1, 95% CI -0.3 to 0.5, 1.9% absolute change, less than 1 point shift on a 0 to 90 scale) post-intervention. In view of the quality of evidence we cannot be certain that biofeedback has a little or no effect on these outcomes. There was very low quality evidence that biofeedback led to more withdrawals from the study (RR 4.08, 95% CI 1.43 to 11.62, 20% absolute risk difference). No adverse events were reported.There was no advantage observed for mindfulness in comparison to usual care for physical functioning (SMD -0.3, 95% CI -0.6 to 0.1, -4.8% absolute change, 4 point shift on a scale 0 to 100), pain (SMD -0.1, CI -0.4 to 0.3, -1.3% absolute change, less than 1 point shift on a 0 to 10 scale), mood (SMD -0.2, 95% CI -0.5 to 0.0, -3.7% absolute change, 2 point shift on a 20 to 80 scale) or withdrawals (RR 1.07, 95% CI 0.67 to 1.72, 2% absolute risk difference) between the two groups post-intervention. However, the quality of the evidence was very low for pain and moderate for mood and number of withdrawals. No studies reported any adverse events.Very low quality evidence revealed that movement therapies in comparison to usual care controls improved pain (MD -2.3, CI -4.2 to -0.4, -23% absolute change) and mood (MD -9.8, 95% CI -18.5 to -1.2, -16.4% absolute change) post-intervention. There was no advantage for physical functioning (SMD -0.2, 95% CI -0.5 to 0.2, -3.4% absolute change, 2 point shift on a 0 to 100 scale), participant withdrawals (RR 1.95, 95% CI 1.13 to 3.38, 11% absolute difference) or adverse events (RR 4.62, 95% CI 0.23 to 93.92, 4% absolute risk difference) between the two groups, however rare adverse events may include worsening of pain.Low quality evidence revealed that relaxation based therapies in comparison to usual care controls showed an advantage for physical functioning (MD -8.3, 95% CI -10.1 to -6.5, -10.4% absolute change) and pain (SMD -1.0, 95% CI -1.6 to -0.5, -3.5% absolute change, 2 point shift on a 0 to 78 scale) but not for mood (SMD -4.4, CI -14.5 to 5.6, -7.4% absolute change) post-intervention. There was no difference between the groups for number of withdrawals (RR 4.40, 95% CI 0.59 to 33.07, 31% absolute risk difference) and no adverse events were reported. AUTHORS' CONCLUSIONS: Psychological interventions therapies may be effective in improving physical functioning, pain and low mood for adults with fibromyalgia in comparison to usual care controls but the quality of the evidence is low. Further research on the outcomes of therapies is needed to determine if positive effects identified post-intervention are sustained. The effectiveness of biofeedback, mindfulness, movement therapies and relaxation based therapies remains unclear as the quality of the evidence was very low or low. The small number of trials and inconsistency in the use of outcome measures across the trials restricted the analysis.

Daytime napping associated with increased symptom severity in fibromyalgia syndrome.

BACKGROUND: Previous qualitative research has revealed that people with fibromyalgia use daytime napping as a coping strategy for managing symptoms against clinical advice. Yet there is no evidence to suggest whether daytime napping is beneficial or detrimental for people with fibromyalgia. The purpose of this study was to explore how people use daytime naps and to determine the links between daytime napping and symptom severity in fibromyalgia syndrome. METHODS: A community based sample of 1044 adults who had been diagnosed with fibromyalgia syndrome by a clinician completed an online questionnaire. Associations between napping behavior, sleep quality and fibromyalgia symptoms were explored using Spearman correlations, with possible predictors of napping behaviour entered into a logistic regression model. Differences between participants who napped on a daily basis and those who napped less regularly, as well as nap duration were explored. RESULTS: Daytime napping was significantly associated with increased pain, depression, anxiety, fatigue, memory difficulties and sleep problems. Sleep problems and fatigue explained the greatest amount of variance in napping behaviour, p < 0.010. Those who engaged in daytime naps for >30 minutes had higher memory difficulties (t = -3.45) and levels of depression (t = -2.50) than those who napped for shorter periods (<30 mins) (p < 0.010). CONCLUSIONS: Frequent use and longer duration of daytime napping was linked with greater symptom severity in people with fibromyalgia. Given the common use of daytime napping in people with fibromyalgia evidence based guidelines on the use of daytime napping in people with chronic pain are urgently needed.

Bridging the gap between goal intentions and actions: a systematic review in patient populations.

PURPOSE: To evaluate the evidence for the effectiveness of if-then implementation intentions (if-then plans) in adult patient populations. Outcomes of interest included adherence, goal pursuit and physical health outcomes. METHODS: Keywords were used to search electronic databases without date or language restrictions (up to 30 April 2014). Studies were included if they (1) concerned a patient population; (2) used if-then plans as a sole intervention or as part of treatment, therapy or rehabilitation; (3) if they were randomised controlled trials. The PEDro scale was used to evaluate study quality. Guidance as set out by the Cochrane Collaboration was used. Two reviewers independently extracted data, discrepancies were discussed and if required referred to a third reviewer. RESULTS: In total, 18 of the 2141 articles were identified as potentially relevant and four studies of people with epilepsy, chronic back pain, stroke and obesity met the inclusion criteria. People who form if-then plans achieved better outcomes on epilepsy and stroke medication adherence and physical capacity than controls. CONCLUSIONS: Of the four studies that used an if-then plan, only one (people with epilepsy) looked at the intervention as a stand-alone strategy. Further research needs to explore if this simple approach improves rehabilitation outcomes and is a helpful and feasible strategy for people experiencing disabilities. Implications for Rehabilitation Steps involved in achieving goals, such as doing exercises or completing other goal related tasks, can be compromised for people with chronic health conditions particularly resulting from difficulties in self-regulating behaviour. If-then plans are implementation intention tools aimed at supporting people to deal more effectively with self-regulatory problems that might undermine goal striving and goal attainment, and have been found to be effective in health promotion and health behaviour change. This systematic literature review identified four studies completed with patient populations, with three demonstrating effectiveness. If-then plans provide an opportunity for clinicians to develop better ways of implementing rehabilitation.

Fibromyalgia syndrome and chronotype: late chronotypes are more affected.

Sleep has strong links to the symptomology of fibromyalgia syndrome (FMS), a diffuse musculoskeletal pain disorder. Information about the involvement of the circadian clock is, however, sparse. In this study, 1548 individuals with FMS completed an online survey containing questions on demographics, stimulant consumption, sleep quality, well-being and subjective pain, chronotype (assessed by the Munich ChronoType Questionnaire, MCTQ), and FMS impact. Chronotype (expressed as the mid-sleep-point on free days, corrected for sleep deficit on workdays, MSF(sc)) significantly correlated with stress-ratings, so-called "memory failures in everyday life," fatigue, FMS impact, and depression but not with anxiety. When chronotypes were categorized into 3 groups (early, intermediate, late), significant group differences were found for sum scores of perceived stress, memory failures in everyday life, fatigue, FMS impact, and depression but not anxiety, with late chronotypes being more affected than early chronotypes. Sleepiness ratings were highest in early chronotypes. Challenges of sleep quality and subjective pain were significantly increased in both early and late chronotypes. The results show that according to their reports, late chronotypes are more affected by fibromyalgia.

Women with fibromyalgia syndrome in New Zealand: the symptom experience.

AIMS: Diagnosis and treatment of fibromyalgia syndrome (FMS) currently focuses on the experience of widespread pain. However, the symptom experience described by patients with FMS in clinical practice is far more diverse. This study aims identify the most common and severe symptoms in female patients diagnosed with FMS. METHODS: This study interviewed 56 patients diagnosed with fibromyalgia syndrome about their symptoms using the Clinical Interview Schedule--Revised. RESULTS: The most frequent and disabling symptoms reported by participants were fatigue, sleep disturbance and cognitive difficulties. CONCLUSIONS: These findings highlight the need for a range of symptoms to be considered in the assessment and treatment of FMS to help improve patient outcomes.

'This constant being woken up is the worst thing' - experiences of sleep in fibromyalgia syndrome.

PURPOSE: Sleep disturbance affects a high proportion of people with fibromyalgia syndrome (FMS). This study aims to explore people's perceptions of their sleep quality and the influence sleep has on their symptoms and daily lives. METHOD: Semi-structured interviews were conducted with sixteen participants diagnosed with primary FMS, covering all aspects of the sleep experience. The audio recorded qualitative interviews were transcribed verbatim and analysed using interpretative phenomenological analysis. RESULTS: Poor sleep dominated participants' lives, affecting levels of pain and fatigue, engagement in daily activities and ability to cope. Participants reported experiencing blocks of sleep, with the most profound difficulty for participants being able to go back to sleep after a night time awakening. They also felt a lack of control in their ability to manage their sleep difficulties and use of day-time napping appeared to be the only perceived beneficial coping strategy for relieving daytime sleepiness and symptoms of fatigue. CONCLUSIONS: Greater emphasis on screening for sleep disorders and how to manage poor sleep is needed in rehabilitation programmes provided for patients with FMS.

The effectiveness of smoking cessation interventions prior to surgery: a systematic review.

The objective of this review was to evaluate the effectiveness of smoking cessation interventions prior to surgery and examine smoking cessation rates at 6 months follow-up. The Cochrane Library Database, PsycINFO, EMBASE, Medline, and Cinahl databases were searched using the terms: smok$, smoking cessation, tobacco, cigar$, preop$, operati$, surg$, randomi*ed control$ trial, intervention, program$, cessation, abstinen$, quit. Further articles were obtained from reference lists. The search was limited to articles on adults, written in English and published up to December 2006. Only randomized control trials (RCTs) that incorporated smoking cessation interventions to patients awaiting elective surgery were included. Seven studies met the inclusion criteria. Methodological quality was assessed by all the authors. The findings revealed that short-term quit rates (or a reduction by more than half of normal daily rate) ranged from 18% to 93% in patients receiving a smoking intervention (mean 55%), compared with a range of 2%-65% of controls (mean = 27.7%). Two studies examined smoking status at 6 months but these revealed no significant difference in abstinence rates between patients who had received an intervention and those that had not. Studies that incorporated counseling in addition to nicotine replacement therapy appeared to show greater benefits. It is concluded that smoking cessation interventions prior to surgery are effective in helping patients to quit smoking. However, such effects appear to be short-lived. Future research needs to examine intervention and patient factors to see whether tailoring the smoking cessation intervention specifically to the patient improves overall abstinence rates.

Dysfunctional beliefs, stress and sleep disturbance in fibromyalgia.

OBJECTIVE: To explore sleep-related dysfunctional beliefs, stress levels and sleep quality in patients with fibromyalgia in comparison to healthy controls. METHODS: One hundred sixty-six participants (83 patients with fibromyalgia and 83 healthy controls) completed self-report measures exploring beliefs and attitudes about sleep, perceived stress, sleep quality and levels of pain and fatigue. RESULTS: Relative to healthy controls, patients with fibromyalgia revealed significantly higher levels of dysfunctional beliefs and attitudes about sleep and perceived stress. High dysfunctional beliefs were significantly associated with poorer sleep quality and high perceived stress was significantly related to higher sleep disturbances and daytime dysfunction. CONCLUSIONS: Beliefs about sleep and perceived stress play a significant role in the sleep quality of patients with fibromyalgia. Interventions to improve sleep quality for people with fibromyalgia need to identify and address dysfunctional beliefs about sleep and incorporate stress management approaches.

Exploring the role of sleep and coping in quality of life in fibromyalgia.

OBJECTIVE: The objective of this study was to explore the effect of sleep and coping on health-related quality of life in fibromyalgia syndrome (FMS). METHODS: Patients diagnosed with FMS (N=101) completed the Positive and Negative Affect Schedule, the Pittsburgh Sleep Quality Index, the COPE, and the Medical Outcomes Study--Short-Form Health Survey for the previous month. RESULTS: Poor sleep quality was reported by 99% of participants. Sleep quality was significantly predictive of pain, fatigue, and social functioning in patients with FMS. Active coping, planning, acceptance, and seeking instrumental and emotional social support were not predictive of health outcomes in FMS. However, the use of restraint coping was predictive of poorer physical functioning. CONCLUSION: Sleep quality has significant implications for health-related quality of life in FMS. The use of coping strategies contributed little to the models' ability to predict health outcomes in FMS. Interventions designed to improve sleep quality may help to improve health-related quality of life for patients with FMS.

Effects of preoperative smoking cessation on the incidence and risk of intraoperative and postoperative complications in adult smokers: a systematic review.

OBJECTIVES: To establish the effect of preoperative smoking cessation on the risk of postoperative complications, and to identify the effect of the timing of preoperative cessation. DATA SOURCES: The Cochrane Library Database, PsycINFO, EMBASE, Medline, and CINAHL databases were searched, using the terms: "smoking", "smoking-cessation", "tobacco-use", "tobacco-abstinence", "cigarett$", "complication$", "postoperative-complication$", "preoperative", "perioperative" and "surg$". Further articles were obtained from reference lists. The search was limited to articles on adults, written in English and published up to November 2005. STUDY SELECTION: Prospective cohort designs exploring the effects of preoperative smoking cessation on postoperative complications were included. Two reviewers independently scanned abstracts of relevant articles to determine eligibility. Lack of agreement was resolved through discussion and consensus. Twelve studies met the inclusion criteria. DATA EXTRACTION: Methodological quality was assessed by both reviewers, exploring validation of smoking status, clear definition of the period of smoking cessation, control for confounding variables and length of follow-up. DATA SYNTHESIS: Only four of the studies specified the exact period of smoking cessation, with six studies specifying the length of the follow-up period. Five studies revealed a lower risk or incidence of postoperative complications in past smokers than current smokers or reported that there was no significant difference between past smokers and non-smokers. CONCLUSIONS: Longer periods of smoking cessation appear to be more effective in reducing the incidence/risk of postoperative complications; there was no increased risk in postoperative complications from short term cessation. An optimal period of preoperative smoking cessation could not be identified from the available evidence.