Periodontitis is associated with decreased experimental pressure pain tolerance: The Tromsø Study 2015-2016.

AIM: To assess the relationship between periodontitis and experimental pain tolerance. MATERIALS AND METHODS: Participants from the population-based seventh survey of the Tromsø Study with data on periodontitis were included (n = 3666, 40-84 years old, 51.6% women). Pain tolerance was assessed through (i) pressure pain tolerance (PPT) test with a computerized cuff pressure algometry on the leg, and (ii) cold-pressor tolerance (CPT) test where one hand was placed in circulating 3°C water. Cox proportional hazard regression was used to assess the association between periodontitis and pain tolerance adjusted for age, sex, education, smoking and obesity. RESULTS: In the fully adjusted model using the 2012 Centers for Disease Control/American Academy of Periodntology case definitions for surveillance of periodontitis, moderate (hazard ratio [HR] = 1.09; 95% confidence interval [CI]: 1.01, 1.18) and severe (HR = 1.25, 95% CI: 1.11, 1.42) periodontitis were associated with decreased PPT. Using the 2018 classification of periodontitis, having Stage II/III/IV periodontitis was significantly associated with decreased PPT (HR = 1.09; 95% CI: 1.01, 1.18) compared with having no or stage I periodontitis. There were no significant associations between periodontitis and CPT in fully adjusted models. CONCLUSIONS: Moderate and severe periodontitis was associated with experimental PPT.

The medication-based Rx-Risk Comorbidity Index and risk of hip fracture - a nationwide NOREPOS cohort study.

BACKGROUND: Few previous studies have assessed overall morbidity at the individual level with respect to future risk of hip fracture. The aim of this register-based cohort study was to examine the association between morbidity measured by the medication-based Rx-Risk Comorbidity Index (Rx-Risk) and the risk of first hip fracture. METHODS: Individual-level data on medications dispensed from pharmacies (2005-2016) was retrieved from the Norwegian Prescription Database and used to calculate Rx-Risk for each calendar year. Information on first hip fractures (2006-2017) was obtained from a nationwide hip fracture database. Individuals ≥ 51 years who filled at least one prescription during the study period comprised the population at risk. Using Rx-Risk as a time-varying exposure variable, relative risk estimates were obtained by a negative binomial model. RESULTS: During 2006-2017, 94,104 individuals sustained a first hip fracture. A higher Rx-Risk was associated with increased risk of hip fracture within all categories of age and sex. Women with the highest Rx-Risk (> 25) had a relative risk of 6.1 (95% confidence interval (CI): 5.4, 6.8) compared to women with Rx-Risk ≤ 0, whereas the corresponding relative risk in women with Rx-Risk 1-5 was 1.4 (95% CI: 1.3, 1.4). Similar results were found in men. Women > 80 years with Rx-Risk 21-25 had the highest incidence rate (514 (95% CI: 462, 566) per 10, 000 person years). The relative increase in hip fracture risk with higher Rx-Risk was most pronounced in the youngest patients aged 51-65 years. CONCLUSIONS: Rx-Risk is a strong predictor of hip fracture in the general outpatient population and may be useful to identify individuals at risk in a clinical setting and in future studies.

Does pain tolerance mediate the effect of physical activity on chronic pain in the general population? The Tromsø Study.

ABSTRACT: Knowledge is needed regarding mechanisms acting between physical activity (PA) and chronic pain. We investigated whether cold pain tolerance mediates an effect of leisure-time physical activity on the risk of chronic pain 7 to 8 years later using consecutive surveys of the population-based Tromsø Study. We included participants with information on baseline leisure-time PA (LTPA) and the level of cold pressor-assessed cold pain tolerance, who reported chronic pain status at follow-up as any of the following: chronic pain for ≥3 months, widespread chronic pain, moderate-to-severe chronic pain, or widespread moderate-to-severe chronic pain. We included 6834 participants (52% women; mean age, 55 years) in counterfactual mediation analyses. Prevalence decreased with severity, for example, 60% for chronic pain vs 5% for widespread moderate-to-severe chronic pain. People with one level higher LTPA rating (light to moderate or moderate to vigorous) at baseline had lower relative risk (RR) of 4 chronic pain states 7 to 8 years later. Total RR effect of a 1-level LTPA increase was 0.95 (0.91-1.00), that is, -5% decreased risk. Total effect RR for widespread chronic pain was 0.84 (0.73-0.97). Indirect effect for moderate-to-severe chronic pain was statistically significant at RR 0.993 (0.988-0.999); total effect RR was 0.91 (0.83-0.98). Statistically significantly mediated RR for widespread moderate-to-severe chronic pain was 0.988 (0.977-0.999); total effect RR was 0.77 (0.64-0.94). This shows small mediation of the effect of LTPA through pain tolerance on 2 moderate-to-severe chronic pain types. This suggests pain tolerance to be one possible mechanism through which PA modifies the risk of moderate-to-severe chronic pain types with and without widespread pain.

The costs of chronic pain-Long-term estimates.

BACKGROUND: Chronic pain is a condition with severe impact on many aspects of life, including work, functional ability and quality of life, thereby reducing physical, mental and social well-being. Despite the high prevalence and burden of chronic pain, it has received disproportionally little attention in research and public policy and the societal costs of chronic pain remain largely unknown. This study aimed to describe the long-term healthcare and work absence costs of individuals with and without self-identified chronic pain. METHODS: The study population were participants in two Norwegian population health studies (HUNT3 and Tromsø6). Participants were defined as having chronic pain based on a self-reported answer to a question on chronic pain in the health studies in 2008. Individuals in the study population were linked to four national register databases on healthcare resource use and work absence. RESULTS: In our study, 36% (n = 63,782) self-reported to have chronic pain and the average years of age was 56.6. The accumulated difference in costs between those with and without chronic pain from 2010 to 2016 was €55,003 (CI: 54,414-55,592) per individual. Extrapolating this to the entire population suggests that chronic pain imposes a yearly burden of 4% of GDP. Eighty per cent of the costs were estimated to be productivity loss. CONCLUSION: Insights from this study can provide a greater understanding of the extent of healthcare use and productivity loss by those with chronic pain and serve as an important basis for improvements in rehabilitation and quality of care, and the education of the public on the burden of chronic pain. SIGNIFICANCE: This was the first study to estimate the economic burden associated with chronic pain in the general population using linked individual-level administrative data and self-reported survey answers. We provide calculations showing that annual costs of chronic pain may be as high as €12 billion or 4% of GDP. Findings from this study highlight the need for a greater understanding of the substantial healthcare use and productivity losses among individuals with chronic pain.

Vitamin D Status During Adolescence and the Impact of Lifestyle Changes: 2 Years' Follow-up From the Fit Futures Study.

CONTEXT: Longitudinal data regarding vitamin D status in adolescence is scarce. This study presents population-based data from an Arctic adolescent population (n = 589) at 16 and 18 years. OBJECTIVE: The aims of this study were to investigate changes in vitamin D status during 2 years in adolescence, and whether lifestyle changes were associated with serum 25-hydroxyvitamin D (s-25(OH)D) at follow-up. METHODS: Fit Futures is a longitudinal study at 69°N in Norway. Participants had their s-25(OH)D levels analyzed in their first and third year of upper secondary school (median age 16 and 18 years), in Fit Futures 1 (FF1) and Fit Futures 2 (FF2), respectively. Self-reported lifestyle habits were registered through questionnaires. The association between lifestyle changes and s-25(OH)D levels at follow-up were calculated by regression analyses, controlling for baseline s-25(OH)D levels. RESULTS: Longitudinal data were available for 309 girls and 280 boys. The proportion of adolescents with s-25(OH)D <50 nmol/L were 73.7% in FF1 and 77.1% in FF2, while the proportion <30 nmol/L constituted 35.7% in FF1 and 40.9% in FF2. Of those with s-25(OH)D <30 nmol/L (severe vitamin D deficiency) in FF1, 73.3% remained severely deficient in FF2. Among boys, an increase in UV exposure was significantly associated with higher s-25(OH)D levels in FF2 (beta; CI [nmol/L] 12.9; 9.1, 16.7). In girls, decreased vitamin/mineral supplement intake was significantly associated with lower s-25(OH)D at FF2 (-6.7; -10.2, -3.1), while increased UV (10.8; 7.0, 14.7) and combined hormonal contraceptive exposure (12.1; 6.0, 18.1) in FF2 was significantly associated with higher s-25(OH)D levels in FF2. CONCLUSION: Severe vitamin D deficiency was prevalent throughout adolescence. Lifestyle changes may alter s-25(OH)D levels in this age group.

The role of neuroticism and pain in dental anxiety: A twin study.

OBJECTIVES: Accumulating evidence has revealed that dental anxiety is robustly associated with dental care-related pain and discomfort, but also with the personality trait of neuroticism (i.e. the relatively stable disposition to experience the world as distressing, threatening and unsafe). However, there is a near absence of research on these risk factors in samples for which genetic information is available. With the aim of arriving at a more refined understanding of dental anxiety, this twin cohort study assessed genetic and environmental influences on neuroticism, dental care-related pain and dental anxiety, and the relation between these phenotypes. METHODS: Participants were recruited from the Norwegian Twin Registry, and data collections were carried out in 1992-98 (Time 1) and 2011 (Time 2). Well-validated questionnaires were used to assess the study variables, including Corah's Dental Anxiety Scale, the Numerical Pain Rating Scale, the NEO Personality Inventory Revised (Time 2) and Eysenck's Personality Questionnaire (Time 1). Pearson correlation analysis and generalized estimating equations (GEE) were used to investigate phenotypic associations. Analyses of genetic and environmental influences were performed using Cholesky modelling. RESULTS: A total of 746 monozygotic (MZ) and 770 dizygotic (DZ) twins in the age group of 50-65 participated in the study. Moderate estimates of heritability for dental anxiety (0.29), treatment-related pain (0.24) and neuroticism (0.45-0.54) were found. Cholesky modelling showed furthermore that neuroticism assessed at Time 1 and Time 2 was related to dental anxiety and pain via both genetic and individual-specific environmental pathways, albeit not very strongly. The particularly high phenotypic correlation observed between dental care-related pain and anxiety (r = .68) was explained by both overlapping genetic and individual-specific environmental influences (the genetic and environmental correlations were .84 and .63 respectively). CONCLUSIONS: The findings provide deeper insight into the aetiology of dental anxiety and confirm that while it is strongly linked to treatment-related pain experiences, this relation is to a considerable degree independent of general negative affectivity/neuroticism.

Consistent pattern between physical activity measures and chronic pain levels: the Tromsø Study 2015 to 2016.

ABSTRACT: Epidemiological literature on the relationship between physical activity and chronic pain is scarce and inconsistent. Hence, our aim was to assess the relationship applying comprehensive methodology, including self-reported and accelerometer measures of physical activity and different severity levels of chronic pain. We used data from the Tromsø Study (2015-2016). All residents in the municipality, aged 40 years and older were invited to participate (n = 32,591, 51% women). A total of 21,083 (53%) women reported on questionnaires. Additionally, 6778 participants (54% women) were invited to wear accelerometers (6125 with complete measurements). Our exposure measures were self-reported leisure time physical activity, exercise frequency, duration, and intensity and 2 accelerometer measures (steps per day and minutes of moderate to vigorous physical activity per day). Outcome measurements were chronic pain and moderate-to-severe chronic pain. We used Poisson regression to estimate chronic pain prevalence and prevalence ratios for each physical activity measure, with adjustments for sex, age, education level, smoking history, and occupational physical activity. Our main analyses showed an inverse dose-response relationship between all physical activity measures and both severity measures of chronic pain, except that the dose-response relationship with exercise duration was only found for moderate-to-severe pain. All findings were stronger for the moderate-to-severe pain outcomes than for chronic pain. Robustness analyses gave similar results as the main analyses. We conclude that an inverse dose-response association between physical activity and chronic pain is consistent across measures. To summarize, higher levels of physical activity is associated with less chronic pain and moderate-to-severe chronic pain.

Accumulation of health complaints is associated with persistent musculoskeletal pain two years later in adolescents: The Fit Futures study.

There is limited knowledge on the association between different health complaints and the development of persistent musculoskeletal pain in adolescents. The aims of this study were to assess whether specific health complaints, and an accumulation of health complaints, in the first year of upper-secondary school, were associated with persistent musculoskeletal pain 2 years later. We used data from a population-based cohort study (the Fit Futures Study in Norway), including 551 adolescents without persistent musculoskeletal pain at baseline. The outcome was persistent musculoskeletal pain (≥3 months) 2 years after inclusion. The following self-reported health complaints were investigated as individual exposures at baseline: asthma, allergic rhinitis, atopic eczema, headache, abdominal pain and psychological distress. We also investigated the association between the accumulated number of self-reported health complaints and persistent musculoskeletal pain 2 years later. Logistic regression analyses estimated adjusted odds ratios (ORs) with 95% confidence intervals (CIs). At the 2-year follow-up, 13.8% (95% CI [11.2-16.9]) reported persistent musculoskeletal pain. Baseline abdominal pain was associated with persistent musculoskeletal pain 2 years later (OR 2.33, 95% CI [1.29-4.19], p = 0.01). Our analyses showed no statistically significant associations between asthma, allergic rhinitis, atopic eczema, headache or psychological distress and persistent musculoskeletal pain at the 2-year follow-up. For the accumulated number of health complaints, a higher odds of persistent musculoskeletal pain at the 2-year follow-up was observed for each additional health complaint at baseline (OR 1.33, 95% CI [1.07-1.66], p = 0.01). Health care providers might need to take preventive actions in adolescents with abdominal pain and in adolescents with an accumulation of health complaints to prevent development of persistent musculoskeletal pain. The potential multimorbidity perspective of adolescent musculoskeletal pain is an important topic for future research to understand the underlying patterns of persistent pain conditions in adolescents.

Social network analysis of Staphylococcus aureus carriage in a general youth population.

OBJECTIVES: Staphylococcus aureus carriage increases the risk of infection. We used social network analysis to evaluate whether contacts have the same S. aureus genotype indicating direct transmission or whether contagiousness is an indirect effect of contacts sharing the same lifestyle or characteristics. METHODS: The Fit Futures 1 study collected data on social contact among 1038 high school students. S. aureus carriage was determined from two nasal swab cultures and the genotype was determined by spa-typing of positive throat swabs. RESULTS: S. aureus carriage and spa-type were transmitted in the social network (P < 0.001). The probability of carriage increased by 5% for each S. aureus positive contact. Male sex was associated with a 15% lower risk of transmission compared to the female sex, although the carriage prevalence was higher for men (36% vs 24%). Students with medium physical activity levels, medium/high alcohol use, or normal weight had a higher number of contacts and an increased risk of transmission (P < 0.002). CONCLUSION: We demonstrated the direct social transmission of S. aureus. Lifestyle factors are associated with the risk of transmission, suggesting the effects of indirect social groups on S. aureus carriage, such as friends having more similar environmental exposures. The male predominance in the carriage is determined by sex-specific predisposing host characteristics as the social transmission is less frequent in males than females. Information on social networks may add to a better understanding of S. aureus epidemiology.

Reduced heart rate variability is related to the number of metabolic syndrome components and manifest diabetes in the sixth Tromsø study 2007-2008.

Both diabetes mellitus (DM) and the metabolic syndrome (MetS) are associated with autonomic neuropathy, which predisposes to cardiac events and death. Measures of heart rate variability (HRV) can be used to monitor the activity of the autonomic nervous system (ANS), and there are strong indications that HRV can be used to study the progression of ANS-related diabetes complications. This study aims to investigate differences in HRV in healthy, MetS and diabetic populations. Based on 7880 participants from the sixth health survey in Tromsø (Tromsø 6, 2007-2008), we found a significant negative association between the number of MetS components and HRV as estimated from short-term pulse wave signals (PRV). This decrease in PRV did not appear to be linear, instead it leveled off after the third component, with no significant difference in PRV between the MetS and DM populations. There was a significant negative association between HbA1c and PRV, showing a decrease in PRV occurring already within the normal HbA1c range. The MetS and DM populations are different from healthy controls with respect to PRV, indicating impaired ANS in both conditions. In the future, a study with assessment of PRV measurements in relation to prospective cardiovascular events seems justified.

Circulating sex-steroids and Staphylococcus aureus nasal carriage in a general male population.

Male sex is associated with higher risk of both colonisation and infection with Staphylococcus aureus (S. aureus). However, the role of sex-steroids in colonisation among men is largely unknown. Thus, the aim of this study was to investigate possible associations between circulating sex-steroids and nasal carriage of S. aureus in a general male population. The population-based Tromsø6 study (2007-2008) included 752 males aged 31-87 years with serum sex-steroids measured by liquid chromatography tandem mass spectrometry and two nasal swab samples for the assessment of S. aureus carriage. Multivariable logistic regression models were used to study the association between sex-steroid concentrations and S. aureus persistent nasal carriage (two positive swabs vs. others), while adjusting for potential confounding factors.S. aureus persistent nasal carriage prevalence was 32%. Among men aged 55 years and above (median age 65 years), there was an inverse dose-response relationship between serum concentration of testosterone and persistent nasal carriage, and carriers had significantly lower mean levels of testosterone (P = 0.028, OR = 0.94 per nmol/l change in testosterone; 95% CI = 0.90-0.98). This association was attenuated when adjusting for body mass index and age (OR = 0.96 per nmol/l change in testosterone; 95% CI = 0.91-1.01). There was no association in the total population. This large population-based study suggests that testosterone levels may be inversely related to S. aureus persistent nasal carriage in older men. Future studies addressing biological mechanisms underlying the male predisposition to S. aureus colonisation and infection may foster preventive interventions that take sex-differences into account.

Reference Curves for Pediatric Endocrinology: Leveraging Biomarker Z-Scores for Clinical Classifications.

CONTEXT: Hormone reference intervals in pediatric endocrinology are traditionally partitioned by age and lack the framework for benchmarking individual blood test results as normalized z-scores and plotting sequential measurements onto a chart. Reference curve modeling is applicable to endocrine variables and represents a standardized method to account for variation with gender and age. OBJECTIVE: We aimed to establish gender-specific biomarker reference curves for clinical use and benchmark associations between hormones, pubertal phenotype, and body mass index (BMI). METHODS: Using cross-sectional population sample data from 2139 healthy Norwegian children and adolescents, we analyzed the pubertal status, ultrasound measures of glandular breast tissue (girls) and testicular volume (boys), BMI, and laboratory measurements of 17 clinical biomarkers modeled using the established "LMS" growth chart algorithm in R. RESULTS: Reference curves for puberty hormones and pertinent biomarkers were modeled to adjust for age and gender. Z-score equivalents of biomarker levels and anthropometric measurements were compiled in a comprehensive beta coefficient matrix for each gender. Excerpted from this analysis and independently of age, BMI was positively associated with female glandular breast volume (ß = 0.5, P < 0.001) and leptin (ß = 0.6, P < 0.001), and inversely correlated with serum levels of sex hormone-binding globulin (SHBG) (ß = -0.4, P < 0.001). Biomarker z-score profiles differed significantly between cohort subgroups stratified by puberty phenotype and BMI weight class. CONCLUSION: Biomarker reference curves and corresponding z-scores provide an intuitive framework for clinical implementation in pediatric endocrinology and facilitate the application of machine learning classification and covariate precision medicine for pediatric patients.

To tolerate weather and to tolerate pain: two sides of the same coin? The Tromsø Study 7.

ABSTRACT: It is a common belief that weather affects pain. Therefore, we hypothesized that weather can affect pain tolerance. This study used data from over 18,000 subjects aged 40 years or older from the general population, who participated in the Tromsø Study 7. They underwent a one-time assessment of cuff algometry pressure pain tolerance (PPT) and cold pain tolerance (CPT), tested with a cold pressor test. The results showed a clear seasonal variation in CPT. The rate of withdrawal in the cold pressor test was up to 75% higher in months in the warmer parts of the year compared with January 2016. There was no seasonal variation in PPT. The study not only found a nonrandom short-term variation in PPT but also indications of such a variation in CPT. The intrinsic timescale of this short-term variation in PPT was 5.1 days (95% % confidence interval 4.0-7.2), which is similar to the observed timescales of meteorological variables. Pressure pain tolerance and CPT correlated with meteorological variables, and these correlations changed over time. Finally, temperature and barometric pressure predicted future values of PPT. These findings suggest that weather has a causal and dynamic effect on pain tolerance, which supports the common belief that weather affects pain.

Shift work, low-grade inflammation, and chronic pain: a 7-year prospective study.

OBJECTIVES: We investigated prospective associations of shift work with chronic pain and C-reactive protein (CRP), an indicator of inflammation. Furthermore, we elucidated CRP as a possible mediator and/or moderator of effects of shift work on pain. METHODS: Data from a 7 years follow-up study were analyzed (N = 2323). Shift work and chronic pain of "neck/shoulder", "arm/hand", "upper back", "low back", "hip/leg/feet", and "other regions" were measured by questionnaires. "Chronic widespread pain", "number of chronic pain sites", and "any chronic pain" were computed. CRP was measured in serum samples. Logistic and Poisson regressions were conducted. Mediation was assessed by casual mediation analyses and moderation by the Relative Excess Risk due to Interaction (RERI). RESULTS: Shift work was not associated with any chronic pain variable and no mediation was detected. CRP was associated with low back pain, hip/leg pain, and "number of pain sites", and also with the combination of shift work and CRP of 1-2.99 mg/L (compared to: no shiftwork and CRP < 1). Additionally, shiftwork and CRP 1-2.99 mg/L was associated with risk of "any chronic pain" (OR: 1.76, 95% CI: 1.12, 2.85), which was not associated with CRP alone. Moderation analyses suggested the risks for "any chronic pain" and "number of pain regions" increased when individuals with elevated CRP worked shifts-beyond what the separate effects of CRP and shift would suggest. CONCLUSIONS: We found no evidence of shift work in general affecting CRP or chronic pain. However, shift work and elevated CRP combined may influence chronic pain.

Circulating sex-steroids and Staphylococcus aureus nasal carriage in a general female population.

OBJECTIVE: Staphylococcus aureus is a major human pathogen, and nasal carriers have an increased risk for infection and disease. The exploration of host determinants for nasal carriage is relevant to decrease infection burden. Former studies demonstrate lower carriage prevalence in women and among users of progestin-only contraceptives. The aim of this study was to investigate the possible associations between circulating sex-steroid hormones and nasal carriage of Staphylococcus aureus in a general population. METHODS: In the population-based sixth Tromsø study (2007-2008) nurses collected nasal swab samples from 724 women aged 30-87 not using any exogenous hormones, and 700 of the women had a repeated nasal swab taken (median interval 28 days). We analysed a panel of serum sex-steroids by liquid chromatography tandem mass spectrometry, and collected information about lifestyle, health and anthropometric measures. Multivariable logistic regression was used to study the association between circulating sex-steroids and Staphylococcus aureus carriage (one swab) and persistent carriage (two swabs), while adjusting for potential confounding factors. Women in luteal phase were excluded in the analysis of androgens. RESULTS: Staphylococcus aureus persistent nasal carriage prevalence was 22%. One standard deviation increase in testosterone and bioavailable testosterone was associated with lower odds of persistent nasal carriage, (OR = 0.57; 95% CI = 0.35-0.92 and OR = 0.52, 95% CI = 0.30-0.92) respectively. Analysis stratified by menopause gave similar findings. Persistent carriers had lower average levels of androstenedione and DHEA, however, not statistically significant. CONCLUSION: This large population-based study supports that women with lower levels of circulating testosterone may have increased probability of Staphylococcus aureus persistent carriage.

Are labor pain and birth experience associated with persistent pain and postpartum depression? A prospective cohort study.

Background and aims A considerable research-literature focuses on pain during labor and associations with postpartum persistent pain and depression, with findings pointing in various directions. The aim of this study was to examine the role of labor pain and overall birth experience in the development of pain and depression 8 weeks after delivery. Methods The study sample was drawn from the Akershus Birth Cohort. Data from multiple sources were used, including the hospital's birth record (n = 4,391), questionnaire data from gestational week 17 of pregnancy (n = 3,752), 8 weeks postpartum (n = 2,217), and two questions about pain and birth experience asked within 48 h after delivery (n = 1,221). The Edinburgh Postnatal Depression Scale was used to measure postpartum depression, a single question was used to measure persistent pain 8 weeks postpartum, while pain and birth experience were measured by numeric rating scales. A history of pre-pregnant depression and chronic pain were measured through self-report questions in gestational week 17. A total of 645 women had complete data from all sources. We applied multiple imputation techniques to handle missing responses on the two questions about pain and birth experience. Results The results showed that neither labor pain nor birth experience were associated with persistent pain 8 weeks postpartum, whereas pain before pregnancy (OR 3.70; 95% CI 2.71-5.04) and a history of depression (OR 2.31; 95% CI 1.85-2.88) were statistically significant predictors of persistent pain. A negative birth experience was significantly (OR 1.16; 95% CI 1.04-1.29) associated with postpartum depression, whereas labor pain intensity was not. A history of depression (OR 3.95; 95% CI 2.92-5.34) and pre-pregnancy pain (OR 2.03; 95% CI 1.37-3.01) were important predictors of postpartum depression 8 weeks after delivery. Conclusions and implications Whilst the relationship between labor pain intensity and postpartum pain and depression remain unclear, our results do imply the need to screen for previous depression and chronic pain conditions in pregnant women, as well as consider preventive measures in those who screen positive.

The Graphical Index of Pain: a new web-based method for high-throughput screening of pain.

This article is the first to present the Graphical Index of Pain (GRIP), a new user-friendly web-based method for high-throughput screening of pain. The long-term goal of the method is to improve global standardization of pain measurements. GRIP consists of a hierarchical body map with 10 first-tier body regions, and a second tier with multiple pain loci (167 among men, 168 among women), which provides detailed information about pain location and distribution. Follow-up questions for first-tier regions include the following pain characteristics: onset, episode frequency, episode duration (including constant pain), intensity, bothering, depth of pain, and effects on sleep and daily activities. The first implementation of GRIP was in the Tromsø Study (2015-2016), a population-based study of adults aged 40 to 99 years. In total, 21,083 individuals participated in the study, and 96% (n = 20,263; age 40-96 years) completed GRIP. Pain intensity at first-tier regions and pain location and distribution at second-tier regions are in this article presented by sex-stratified customized heat maps showing large sex difference. Mean time to mark the first- and second-tier regions was 74 seconds. In conclusion, GRIP allows for high-resolution assessment and presentation of pain location and distribution with minimal use of time.