Longitudinal changes of psychological distress among childhood cancer survivors: The Swiss Childhood Cancer Survivor Study.

BACKGROUND: Childhood cancer survivors may experience psychological distress due to the disease, cancer treatments, and potential late effects. Limited knowledge exists regarding longitudinal changes in psychological distress after childhood cancer. We aimed to determine changes in psychological distress over time and explore determinants of changes. METHODS: The Swiss Childhood Cancer Survivor Study collected data at baseline (2007-2009) and follow-up (2010-2012). Psychological distress was measured using the Brief Symptom Inventory 18 (BSI-18), including three symptom scales (somatization, depression, anxiety) and an overall distress index (Global Severity Index, GSI). Sum-scores were T-standardized (mean = 50; standard deviation [SD] = 10). Survivors with a score ≥57 on the GSI or two symptom scales were classified as cases with distress. We used linear mixed effects regression to identify potential sociodemographic and clinical determinants of change in psychological distress. RESULTS: We analyzed 696 survivors at baseline (mean age = 24 years [SD = 4], 49% females, mean time since diagnosis = 16 years [SD = 4]). On follow-up (2.4 years, SD = 1), 317 survivors were analyzed, including 302 participants with repeated measures. We found that 13% (39/302) were cases at baseline, and 25% (76/302) were cases on follow-up. Those older at study and longer since diagnosis, females, diagnosed with central nervous system (CNS) tumors, and those reporting late effects were more likely to experience higher levels of distress. Females and unemployed are at higher risk for developing or persisting psychological distress than males and those who are employed or in training. CONCLUSION: We observed an increase in psychological distress score over time, with higher proportion of psychological distress on follow-up. Anticipatory guidance and screening should be implemented in regular follow-up care.

Placental human papillomavirus infections and adverse pregnancy outcomes.

INTRODUCTION: Knowledge on prevalence and association of human papillomavirus (HPV) in third trimester placentae and adverse pregnancy outcomes is limited. We investigated the prevalence of placental HPV at delivery, explored urine HPV characteristics associated with placental HPV and whether placental HPV increased the risk adverse pregnancy outcomes. METHODS: Pregnant women were enrolled in the Scandinavian PreventADALL mother-child cohort study at midgestation. Human papillomavirus genotyping was performed on placental biopsies collected at delivery (n = 587) and first-void urine at midgestation and delivery (n = 556). Maternal characteristics were collected by questionnaires at gestational week 18 and 34. Adverse pregnancy outcomes were registered from chart data including hypertensive disorders of pregnancy, gestational diabetes mellitus and newborns small for gestational age. Uni- and multivariable regression models were used to investigate associations. RESULTS: Placental HPV was detected in 18/587 (3 %). Twenty-eight genotypes were identified among the 214/556 (38 %) with midgestational urine HPV. Seventeen of the 18 women with placental HPV were midgestational HPV positive with 89 % genotype concordance. Midgestational high-risk-(HR)-HPV and high viral loads of Any- or HR-HPV were associated with placental HPV. Persisting HPV infection from midgestation to delivery was not associated with placental HPV. Adverse pregnancy outcomes were seen in 2/556 (0.4 %) of women with placental HPV. DISCUSSION: In this general cohort of pregnant women, the prevalence of placental HPV was 3 %, and midgestational urinary HPV 38 %. High HPV viral load increased the risk for placental HPV infections. We observed no increased risk for adverse pregnancy outcomes in women with placental HPV.

Effect of a 1-year physical activity intervention on quality of life, fatigue, and distress in adult childhood cancer survivors-A randomized controlled trial (SURfit).

INTRODUCTION: Childhood cancer survivors (CCS) are at risk of experiencing lower quality-of-life, fatigue, and depression. Few randomized controlled trials have studied the effect of physical activity (PA) on these in adult long-term CCS. This study investigated the effect of a 1-year individualized PA intervention on health-related quality-of-life (HRQOL), fatigue, and distress symptoms in adult CCS. METHODS: The SURfit trial randomized 151 CCS ≥16 years old, <16 at diagnosis and ≥5 years since diagnosis, identified through the Swiss Childhood Cancer Registry. Intervention participants received personalized PA counselling to increase intense PA by ≥2.5 h/week for 1 year. Controls maintained usual PA levels. The authors assessed physical- and mental-HRQOL, fatigue, and distress symptoms at baseline, 3, 6, and 12 months. T-scores were calculated using representative normative populations (mean = 50, standard deviation = 10). Generalized linear mixed-effects models with intention-to-treat (ITT, primary), and three per-protocol allocations were used. RESULTS: At 12 months, ITT (-3.56 larger decrease, 95% confidence interval -5.69 to -1.43, p = .001) and two per-protocol analyses found significantly lower fatigue. Physical-HRQOL improved significantly in two per-protocol analyses at 12 months. No other effects were found. CONCLUSION: SURfit showed that increased intense PA over 1 year improved fatigue in adult CCS. Survivors should be recommended PA to reduce the burden of late-effects.

Physical Activity Among Adolescent Cancer Survivors: The PACCS Study.

OBJECTIVES: Physical activity (PA) may modify risks of late effects after cancer. We aimed to examine levels of PA and sedentary time (ST) in a large, international sample of adolescent childhood cancer survivors in relation to sociodemographic and cancer-related factors and compare levels of PA and ST to reference cohorts. METHODS: Survivors from any cancer diagnosis who had completed cancer treatment ≥1 year ago, aged 9 to 16 years, were eligible for the multicenter Physical Activity in Childhood Cancer Survivors study. PA and ST were measured by ActiGraph GT3X+ accelerometers. We performed linear regression analyses to assess factors associated with moderate-to-vigorous PA (MVPA) and ST, and compared marginal means of total PA, MVPA, and ST in 432 survivors to sex- and age-stratified references (2-year intervals) using immediate t-tests for aggregated data. RESULTS: Among survivors, 34% fulfilled the World Health Organization's PA recommendation of ≥60 min of daily MVPA on average and their ST was 8.7 hours per day. Being female, older, overweight, a survivor of central nervous system tumor, or having experienced relapse were associated with lower MVPA and/or higher ST. Generally, male survivors spent less time in MVPA compared with references, whereas female survivors had similar levels. Both male and female survivors had higher ST than references in nearly all age groups. CONCLUSIONS: The low PA and high ST in this large sample of adolescent childhood cancer survivors is worrisome. Combined, our results call for targeted interventions addressing both PA and ST in follow-up care after childhood cancer.

Effect of a 1-year physical activity intervention on cardiovascular health in long-term childhood cancer survivors-a randomised controlled trial (SURfit).

BACKGROUND: This randomised controlled trial (RCT) assessed the effect of a 1-year, partially supervised, physical activity (PA) intervention on a cardiovascular disease (CVD) risk score in adult survivors of childhood cancer. METHODS: We included childhood cancer survivors ≥16 y at enrolment, <16 y at diagnosis and ≥5 y in remission. The intervention group was asked to perform an additional ≥2.5 h of intense physical activity/week, controls continued exercise as usual; assessments were performed at baseline, 6 months (T6) and 12 months (T12). The primary endpoint was change in a CVD risk score (average z-score of waist circumference, blood pressure, fasting glucose, inverted high-density lipoprotein cholesterol, triglycerides, and inverted cardiorespiratory fitness) from baseline to T12. We performed intention-to-treat (ITT, primary) and 3 per protocol analyses. RESULTS: We randomised 151 survivors (44% females, 30.4 ± 8.6 years). We found a significant and robust reduction of the CVD risk score in the intervention compared to the control group at T6 and T12 across all analyses; with a difference in the reduction of the CVD risk z-score of -0.18 (95% confidence interval -0.29 to -0.06, P = 0.003) at T12 in favour of the intervention group (ITT analysis). CONCLUSIONS: This RCT showed that a long-term PA intervention can reduce CVD risk in long-term survivors of childhood cancer. TRIAL REGISTRATION: Clinicaltrials.gov: NCT02730767.

Renal Safety of Long-term Tenofovir Disoproxil Fumarate Treatment in Patients With Chronic Hepatitis B.

Background: Data on renal safety of tenofovir disoproxil fumarate (TDF) treatment among individuals with chronic hepatitis B (CHB) are inconsistent. The current study aimed to assess the effect of long-term TDF treatment on renal outcomes in adult patients with CHB. Methods: From a CHB cohort in Ethiopia, we included 233 patients treated with TDF and 126 untreated controls. Levels of creatinine and creatinine clearance over time were described in patients with and without TDF treatment. Linear mixed effects models with a treatment × time interaction were used to investigate the effect of TDF on creatinine and creatinine clearance. In treated patients only, change in creatinine and creatinine clearance was estimated separately in the first year as compared with subsequent years via linear mixed effects models. Results: Median follow-up in the treated group was 51 months (IQR, 27-72), and 75% of patients were male (median age, 33 years; IQR, 26-40). Median follow-up in the untreated group was 69 months (IQR, 66-72), and 48% of participants were male (median age, 33 years; IQR, 27-41). We found no change in creatinine over time in TDF-treated patients as compared with a slight increase in untreated patients (P interaction = .003). There was a decrease in creatinine clearance over time in both groups, which was stronger in patients without TDF treatment (P interaction = .007). In TDF-treated patients, changes in creatinine and creatinine clearance occurred mainly within the first 12 months after treatment initiation. Conclusions: This study showed no evidence of long-term renal toxicity of TDF treatment in patients with CHB.

Adherence and contamination in a 1-year physical activity program in childhood cancer survivors: A report from the SURfit study.

PURPOSE: Meeting intervention requirements is crucial in behavioral trials. We examined patterns and predictors of physical activity (PA) adherence and contamination in a 1-year individualized randomized controlled PA behavioral intervention in childhood cancer survivors (CCS). METHODS: CCS aged ≥16 at enrolment, <16 at diagnosis, and ≥5 years in remission were identified from the Swiss Childhood Cancer Registry. We asked participants randomized to the intervention group to perform an additional ≥2.5 h of intense PA/week and controls to continue as usual. Adherence to the intervention was assessed by online diary (adherent if ≥2/3 of individual PA goal reached) and contamination for the control group by pre- and post-questionnaire including PA levels (contaminated if >60 min increase/week in PA). Predictors of adherence/contamination including quality of life (36-Item Short Form Survey) were assessed by questionnaire. We used logistic (control group) and mixed logistic regression models (exercise group) to estimate predictors of study adherence and contamination. RESULTS: One hundred and forty-four survivors (30.4 ± 8.7 years old, 43% females) were included. Adherence was 48% (35/73) in the intervention group, while 17% (12/71) of controls contaminated group allocation. Predictors for PA adherence were female sex (OR 2.35, p = 0.03), higher physical (OR 1.34, p = 0.01) and mental quality of life (OR 1.37, p = 0.001), and week into the intervention (OR 0.98, p < 0.001). Clear differences in PA behavior of adherent and non-adherent participants were seen from week four. No significant predictors for contamination were found for controls. CONCLUSION: Adherence to PA behavior interventions remain challenging in both groups. Further long-term trials should consider intense motivational support within the first month, more detailed data collection for the control group, adjustments to power calculations and other study designs to minimize non-adherence and contamination.

Nevus Count, Pigmentary Characteristics, and Melanoma-specific Mortality among Norwegian Women with Melanoma >1.0 mm Thick.

Little is known about if and how nevi and pigmentation are associated with melanoma-specific mortality. However, increased melanoma awareness in people with lighter pigmentation and many nevi may result in earlier diagnosis of thinner less-lethal tumors. The aim of this study was to investigate associations between nevus count (asymmetrical > 5 mm and small symmetrical), pigmentary characteristics (hair colour, eye colour, skin colour, freckling, pigmentary score), and melanoma-specific mortality in subjects with melanomas > 1 mm. Data from the Norwegian Women and Cancer cohort, established in 1991, with complete follow-up of melanoma patients until 2018 through the Cancer Registry of Norway, were used to estimate hazard ratios with 95% confidence intervals for the associations between nevus count, pigmentary characteristics, and melanoma-specific mortality, stratified by tumor thickness using Cox regression. Estimated hazard ratios consistently indicated a higher risk of melanoma death for those with darker vs lighter pigmentary characteristics in patients with tumors > 1.0-2.0 mm and > 2.0 mm thick (e.g. pigmentary score hazard ratio 1.25, 95% confidence interval (0.74-2.13)). Among women with melanomas > 1.0 mm thick, lighter pigmentation and asymmetrical nevi may be associated with lower melanoma-specific mortality, suggesting that factors that increase the risk of melanoma may also be associated with decreased risk of death from melanoma.

Effect of a physical activity intervention on lower body bone health in childhood cancer survivors: A randomized controlled trial (SURfit).

It remains controversial whether physical activity promotes bone health in childhood cancer survivors (CCS). We aimed to assess the effect of a one-year general exercise intervention on lower body bone parameters of CCS. CCS ≥16 years at enrollment, <16 years at diagnosis and ≥5 years in remission were identified from the national Childhood Cancer Registry. Participants randomized to the intervention group were asked to perform an additional ≥2.5 hours of intense physical activity/week, controls continued exercise as usual. Bone health was assessed as a secondary trial endpoint at baseline and after 12-months. We measured tibia bone mineral density (BMD) and morphology by peripheral quantitative computed tomography and lumbar spine, hip and femoral neck BMD by dual-energy x-ray absorptiometry. We performed intention-to-treat, per protocol, and an explorative subgroup analyses looking at low BMD using multiple linear regressions. One hundred fifty-one survivors (44% females, 7.5 ± 4.9 years at diagnosis, 30.4 ± 8.6 years at baseline) were included. Intention-to-treat analysis revealed no differences in changes between the intervention and control group. Per protocol analyses showed evidence for an improvement in femoral neck and trabecular BMD between 1.5% and 1.8% more in participants being compliant with the exercise program. Trabecular BMD increased 2.8% more in survivors of the intervention group with BMD z-score ≤-1 compared to those starting at z-score >-1. A nonstandardized personalized exercise programs might not be specific enough to promote bone health in CCS, although those compliant and those most in need may benefit. Future trials should include bone stimulating exercise programs targeting risk groups with reduced bone health and motivational features to maximize compliance.

Life-Course Trajectories of Physical Activity and Melanoma Risk in a Large Cohort of Norwegian Women.

Purpose: Physical activity (PA) is a cornerstone in disease prevention and varies throughout life. A pooled analysis of cohort studies and a meta-analysis of cohort studies found positive associations between PA and melanoma risk. However, previous studies focused on PA at specific ages and often lacked information on ultraviolet radiation (UVR) exposure. Using the population-based Norwegian Women and Cancer (NOWAC) cohort, including information on PA and UVR exposure, we estimated life-course PA trajectories from adolescence to adulthood and their associations with melanoma. Methods: Total PA across different domains (recreation, occupation, transport, household) was reported for ages 14 and 30 years, and when responding to the questionnaire (31-76 years) using a 10-point scale, validated to rank PA levels in Norwegian females. We estimated life-course PA trajectories using a latent class mixed model in 152,248 women divided into three subcohorts depending on age at questionnaire completion: 31-39 (n = 27,098), 40-49 (n = 52,515) and ≥50 years (n = 72,635). The unique 11-digit identity number of Norwegian citizens was used to link NOWAC to the Cancer Registry of Norway for information on cancer diagnoses, emigration and death. Associations between PA trajectories and melanoma risk were estimated in each subcohort using multivariable Cox regression. Results: Five classes of individual life-course PA trajectories were identified in subcohort 31-39 years (low, moderate, high, decreasing, increasing PA) and four in subcohorts 40-49 and ≥50 years (low, moderate, high, decreasing PA). No significant association was found between life-course PA trajectories and melanoma risk in any subcohort. Hazard ratios (95% confidence intervals) for the high versus moderate trajectory were 0.92 (0.66-1.29), 1.15 (0.97-1.37) and 0.90 (0.78-1.05) for subcohorts 31-39, 40-49 and ≥50 years, respectively. Conclusion: Our results do not support a positive association between PA and melanoma risk found in previous studies, which is important for public health guidelines promoting regular PA.

Letter to the editor regarding "Covid-19 transmission in fitness centers in Norway - a randomized trial".

In a recently published paper in BMC Public Health we read about a randomized trial on Covid-19 transmission performed in five fitness centers in Oslo, Norway, during the spring of 2020. In our opinion, this study has major shortcomings in design and methodology, which have not been addressed by the authors.

Lifetime Sunburn Trajectories and Associated Risks of Cutaneous Melanoma and Squamous Cell Carcinoma Among a Cohort of Norwegian Women.

Importance: To our knowledge, no study has prospectively investigated sunburn patterns over age periods from childhood to adulthood and their associations with skin cancer risk. Objective: To identify lifetime trajectories of sunburns and compare the association between these trajectories and subsequent risk of cutaneous melanoma and squamous cell carcinoma (cSCC). Design, Setting, and Participants: This population-based cohort study included participants from the Norwegian Women and Cancer Study, established in 1991, with follow-up through 2018. Baseline questionnaires were issued from 1991 to 2007, with follow-up questionnaires every 5 to 7 years. Data analysis was performed from March 16, 2021, to December 4, 2021. Exposures: Participants reported pigmentation factors, sunbathing vacations, and indoor tanning. Annual frequencies of sunburns were reported for childhood, adolescence, and adulthood. Main Outcomes and Measures: Information on cancer diagnoses, emigration, and death were obtained through linkage to the Cancer Registry of Norway using the unique personal identification number of Norwegian citizens. Results: Of the 172 472 women (age range, 31-70 years) who returned questionnaires, 169 768 received questions about sunburns at study inclusion. Five classes (stable low, low-moderate-low, low to high, high to low, and stable high) of individual lifetime sunburn trajectories with similar shapes were estimated in 3 samples up to 39 years (n = 159 773), up to 49 years (n = 153 297), and up to 59 years (n = 119 170). Mean follow-up ranged from 14.3 to 19.5 years in the 3 samples, during which 1252 to 1774 women were diagnosed with incident primary melanoma and 739 to 871 women with incident primary cSCC. With hazard ratios (HRs) and 95% CIs estimated using a Cox proportional hazards model, the stable high and high to low trajectories showed statistically significant increased melanoma and cSCC risks compared with the stable low trajectory across all samples (≤39 years for stable high and high to low trajectories: melanoma: HR, 1.50 [95% CI, 1.28-1.75] and HR, 1.44 [95% CI, 1.20-1.73]; cSCC: HR, 1.51 [95% CI, 1.22-1.87] and HR, 1.47 [95% CI, 1.14-1.91]). Other trajectories showed increased risk, though generally weaker and mainly estimates that were not statistically significant. There was no statistically significant heterogeneity between melanoma and cSCC estimates. Conclusion and Relevance: This cohort study showed that high sunburn frequency throughout life was associated with increased melanoma and cSCC risk. Furthermore, sunburns in childhood are especially important for subsequent risk of these skin cancers. Avoiding sunburns throughout life, in particular in childhood, is therefore crucial.

Physical and functional performance assessment in pediatric oncology: a systematic review.

BACKGROUND: Research indicates reduced physical performance from diagnosis into survivorship of pediatric cancer patients. However, there is no systematic information or guideline available on the methods to assess physical performance and function in this population. The purpose was to systematically compile and describe assessments of physical performance and function in patients and survivors of pediatric cancer, including cardiorespiratory fitness, muscle strength, speed, balance, flexibility, functional mobility, gait and motor performance test batteries. METHODS: We searched the databases PubMed, SPORTDiscus, and Cochrane Database and performed abstract and full-text selection of 2619 articles according to the Cochrane Handbook of Systematic Reviews. Information on patients characteristics, assessments, information on validity and reliability, and relevant references was extracted. RESULTS: In summary, 63 different assessments were found in 149 studies including 11639 participants. Most studies evaluated cardiorespiratory fitness and muscle strength with the majority conducted off treatment. Some outcomes (e.g. speed) and diagnoses (e.g. neuroblastoma) were severely underrepresented. With the exception of gait, leukemia patients represented the largest group of individuals tested. CONCLUSIONS: Insufficient data and patient heterogeneity complicate uniform recommendations for assessments. Our results support researchers and practitioners in selecting appropriate assessment to meet their specific research questions or individual daily practice needs. IMPACT: This systematic review includes 149 studies and provides a comprehensive summary of 63 assessments to evaluate cardiorespiratory fitness, muscle strength, speed, balance, flexibility, functional mobility, gait or motor performance test batteries in patients and survivors of pediatric cancer. We present the most studied fields within the pediatric cancer population, which are cardiorespiratory fitness and muscle strength, off treatment phase, and leukemia patients. We propose research priorities by identification of subgroups in terms of cancer type, phase of treatment, and outcome of interest that are underrepresented in studies currently available.

Sunscreens With High Versus Low Sun Protection Factor and Cutaneous Squamous Cell Carcinoma Risk: A Population-Based Cohort Study.

Evidence on sunscreen use and cutaneous squamous cell carcinoma (cSCC) risk is limited. Most studies have not taken sun protection factor (SPF) into consideration and used nonusers of sunscreen as the reference group. Nonusers are likely a priori at lower cSCC risk than users. No study has investigated the effect of high- versus low-SPF sunscreens on cSCC, appropriately adjusting for time-varying confounding. Using data from the Norwegian Women and Cancer Study (1991-2016), we investigated whether use of SPF ≥15 versus SPF <15 sunscreens reduces cSCC risk. We used a marginal structural Cox proportional hazards model with inverse probability of treatment and censoring weights to estimate hazard ratios (HRs) and 95% confidence intervals (CIs). During follow-up of 148,781 women (mean follow-up, 14.3 years), 653 women were diagnosed with cSCC. The effect on cSCC risk of sunscreens with SPF ≥15 versus SPF <15 was close to the null when used at any latitudes (HR = 1.02, 95% CI: 0.82, 1.27) and when used in lower-latitude settings (HR = 1.05, 95% CI: 0.84, 1.32). In conclusion, we found no indication that sunscreens with SPF ≥15 reduced Norwegian women's cSCC risk more than sunscreens with SPF <15, suggesting that either there is no difference in their effects long-term or the difference is diluted by incorrect application.

A Phase I/II randomized trial of H56:IC31 vaccination and adjunctive cyclooxygenase-2-inhibitor treatment in tuberculosis patients.

Host-directed-therapy strategies are warranted to fight tuberculosis. Here we assess the safety and immunogenicity of adjunctive vaccination with the H56:IC31 candidate and cyclooxygenase-2-inhibitor treatment (etoricoxib) in pulmonary and extra-pulmonary tuberculosis patients in a randomized open-label phase I/II clinical trial (TBCOX2, NCT02503839). A total of 222 patients were screened, 51 enrolled and randomized; 13 in the etoricoxib-group, 14 in the H56:IC31-group, 12 in the etoricoxib+H56:IC31-group and 12 controls. Three Serious Adverse Events were reported in the etoricoxib-groups; two urticarial rash and one possible disease progression, no Serious Adverse Events were vaccine related. H56:IC31 induces robust expansion of antigen-specific T-cells analyzed by fluorospot and flow cytometry, and higher proportion of seroconversions. Etoricoxib reduced H56:IC31-induced T-cell responses. Here, we show the first clinical data that H56:IC31 vaccination is safe and immunogenic in tuberculosis patients, supporting further studies of H56:IC31 as a host-directed-therapy strategy. Although etoricoxib appears safe, our data do not support therapy with adjunctive cyclooxygenase-2-inhibitors.

Physical activity and cutaneous melanoma risk: A Norwegian population-based cohort study.

Physical activity (PA) is an important factor in cancer prevention, but positive association between PA and risk of cutaneous melanoma found in recent studies may complicate this strategy. Ultraviolet radiation (UVR) exposure during outdoor PA is a plausible explanation for a positive association. We investigated the associations between PA, UVR and melanoma risk in the Norwegian Women and Cancer cohort. Overall PA was reported by 151,710 women, aged 30-75 at inclusion, using a validated 10-point-scale at enrolment and during follow-up, together with recent numbers of sunburns, indoor tanning sessions and weeks on sunbathing vacations. Seasonal outdoor walking and seasonal PAs were recorded in subsamples (n = 102,671 and n = 29,077, respectively). Logistic and Cox regression were used. Mean follow-up was 18.5 years, and 1565 invasive incident melanoma cases were diagnosed. Overall PA was inversely associated with sunburns, while positively associated with sunbathing vacations and indoor tanning. Overall PA was not associated with melanoma risk in all body sites combined (ptrend = 0.61), but reduced risk was found in upper limb melanomas (hazard ratio (HR) = 0.70, 95% confidence interval (CI) 0.51-0.96; high versus low PA). Non-significant reduced risks were found for seasonal outdoor walking >2 h/day versus 30-60 min/day (summer HR = 0.81, 95% CI 0.66-1.00; autumn HR = 0.74, 95%CI 0.55-1.01). Seasonal PAs were not associated with melanoma risk. In conclusion, we found positive associations between overall PA and sunbathing vacations and indoor tanning, and, unlike literature, inverse association between overall PA and sunburns. Our results do not support a positive association between PA and melanoma risk in Norwegian women.

High impact physical activity and bone health of lower extremities in childhood cancer survivors: A cross-sectional study of SURfit.

Childhood cancer survivors (CCS) are at risk of reduced bone health and premature osteoporosis. As physical activity with high impact loading (IL-PA) is known to promote bone health, we compared bone densitometry and microstructure between groups of CCS who performed different amounts of physical activities in their daily life. We used baseline data of a single-center PA trial including 161 CCS from the Swiss Childhood Cancer Registry, aged <16 at diagnosis, ≥16 at study and ≥5 years since diagnosis. Lower body bone health was assessed with peripheral quantitative computed tomography (pQCT) and dual-energy X-ray absorptiometry (DXA). Daily IL-PA (duration in activities >2 g acceleration and numbers of vertical impacts/hr >2 g) was captured using hip-worn accelerometers (1-3 weeks). For both IL-PA approaches, we formed low, middle and high activity groups based on tertiles. Bone health of the high and middle active groups was compared to the low active group. 63% of CCS had indication of at least one bone mineral density z-score ≤ -1 measured by pQCT or DXA. The high IL-PA group performing 2.8 min/day or 19.1 impact peaks/hr > 2 g (median) showed about 3-13% better microstructural and densitometric bone health as compared to the low IL-PA group with 0.38 min/day or 0.85 peaks/hr > 2 g. Just a few minutes and repetitions of high IL-PA as easily modifiable lifestyle factor may be sufficient to improve bone health in adult CCS. Future longitudinal research is needed to better understand pattern and dosage of minimal impact loading needed to strengthen bone in growing and adult CCS.