Assuntos
Carcinoma Basocelular , Carcinoma de Células Escamosas , Neoplasias Cutâneas , Classe Social , Humanos , Estudos Transversais , Feminino , Masculino , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/patologia , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/patologia , Pessoa de Meia-Idade , Carcinoma Basocelular/epidemiologia , Carcinoma Basocelular/patologia , Idoso , Adulto , Fatores Sexuais , Fatores Etários , Idoso de 80 Anos ou mais , Grupos Raciais/estatística & dados numéricosRESUMO
Psoriasis (PsO) is a chronic inflammatory skin condition, often accompanied by psoriatic arthritis (PsA) and linked to various comorbidities and increased mortality rates. This study aimed to explore the relationship between PsO and accelerated biological aging, specifically focusing on epigenetic DNA methylation clocks. Using a matched case-control design, 20 PsO cases were selected along with age, race, and sex-matched 20 controls without PsO from the Skin Disease Biorepository at Brown Dermatology, Inc, Providence, Rhode Island. Blood samples retrieved from both groups were analyzed for DNA methylation, and epigenetic ages were calculated using DNA methylation clocks, including Horvath, Hannum, Pheno, SkinBlood, and Grim ages. Generalized estimation equations were employed to test the differences in epigenetic and chronological ages between PsO cases and controls, as well as within various subgroups in comparison to their respective controls. There were no statistically significant differences in epigenetic ages between PsO cases and controls. However, notably, PsO cases with PsA demonstrated an accelerated PhenoAge, compared to their matched controls. This study represents a pioneering investigation into the potential link between PsO and epigenetic aging, shedding light on the possibility of accelerated epigenetic aging in PsA, possibly associated with heightened inflammatory burden. These findings emphasize the systemic impact of PsA on the aging process, prompting the need for deeper exploration into autoimmune pathways, inflammation, and epigenetic modifications underlying PsO pathogenesis and aging mechanisms. Larger-scale studies with diverse populations are imperative to discern PsO subgroups experiencing accelerated biological aging and decipher the intricate interplay between PsO, inflammation, and aging pathways.
Assuntos
Metilação de DNA , Epigênese Genética , Psoríase , Humanos , Estudos de Casos e Controles , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Psoríase/genética , Idoso , Envelhecimento/genética , Artrite Psoriásica/genéticaRESUMO
The Korea Nurses' Health Study (KNHS) is an ongoing, large-scale, prospective cohort study of women nurses, focusing on the effects of occupational, environmental, and lifestyle factors on the health of women. The first KNHS survey was performed in 2013-2014 (n=20,613). As of December 2023, 11 follow-up surveys have been conducted. Participants who were pregnant were asked to participate in the early pregnancy survey (n=2,179) and postpartum survey after giving birth (n=2,790). The main variables included socio-demographic, work-related, lifestyle, physical, mental, and women's health factors. Blood, urine, and toenail samples were collected from a participant subgroup of the first survey (n=1,983). The subgroups of the second survey completed a food frequency questionnaire in 2019 (n=300) and 2021 (n=871). In 2020, a subgroup of the first survey answered a coronavirus disease 2019-related survey (n=975). To examine various health-related factors in young adults, new participants were added to the KNHS cohort in the 11th (n=1,000) and 12th (n=1,002) surveys. The KNHS cohort will help identify health and illness determinants in Korean women. Data can be accessed at https://coda.nih.go.kr/frt/index.do.
Assuntos
Enfermeiras e Enfermeiros , Saúde da Mulher , Humanos , Feminino , República da Coreia/epidemiologia , Adulto , Estudos Prospectivos , Enfermeiras e Enfermeiros/estatística & dados numéricos , Enfermeiras e Enfermeiros/psicologia , COVID-19/epidemiologia , Gravidez , Estudos de Coortes , Inquéritos Epidemiológicos , Nível de Saúde , Adulto Jovem , Pessoa de Meia-IdadeRESUMO
Exposure to solar ultraviolet (UV) radiation and use of UV-emitting tanning devices are known risk factors for skin cancer. Few studies have explored the interaction between these risk factors, namely how the risk of skin cancer increases among those who both have been exposed to high levels of natural sunlight and regularly use tanning beds. Nurses' Health Study II followed 116,430 women, aged 25-42, from 1991 to 2011. Cumulative average UV exposure was based on participants' residences at follow-up periods. History of severe sunburn during ages 15-20 was used as a proxy for early-life sunlight exposure. Tanning bed use in early life data was collected. Participants reported melanoma, basal cell carcinoma (BCC), and squamous cell carcinoma (SCC) diagnoses. We built multivariable Cox regression models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for risk of skin cancer associated with joint effects of sunlight exposure and tanning bed use. Participants with high sunlight exposure and tanning bed use during high school/college had an increased risk of BCC (HR = 1.53, 95% CI 1.37-1.71, Pinteraction=0.01; vs. low sun exposure and no tanning bed use). Participants with a history of severe sunburns and tanning bed use during high school/college were at increased risk of BCC (HR = 1.62, 95% CI 1.47-1.79, Pinteraction=0.02; vs. no sunburns and no tanning bed use). No significant interactions were found between sunlight exposure and tanning bed use on SCC and melanoma risk. We found significant interactions between sunlight exposure and tanning bed use on the risk of BCC.
Assuntos
Carcinoma Basocelular , Carcinoma de Células Escamosas , Melanoma , Neoplasias Cutâneas , Banho de Sol , Luz Solar , Humanos , Feminino , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/epidemiologia , Carcinoma Basocelular/epidemiologia , Carcinoma Basocelular/etiologia , Melanoma/etiologia , Melanoma/epidemiologia , Estudos Prospectivos , Carcinoma de Células Escamosas/epidemiologia , Carcinoma de Células Escamosas/etiologia , Adulto , Luz Solar/efeitos adversos , Fatores de Risco , Banho de Sol/estatística & dados numéricos , Queimadura Solar/epidemiologia , Raios Ultravioleta/efeitos adversos , Modelos de Riscos ProporcionaisRESUMO
BACKGROUND: Bipolar disorder (BD) shows heterogeneous illness presentation both cross-sectionally and longitudinally. This phenotypic heterogeneity might reflect underlying genetic heterogeneity. At the same time, overlapping characteristics between BD and other psychiatric illnesses are observed at clinical and biomarker levels, which implies a shared biological mechanism between them. Incorporating these two issues in a single study design, this study investigated whether phenotypically heterogeneous subtypes of BD have a distinct polygenic basis shared with other psychiatric illnesses. METHODS: Six lifetime phenotype dimensions of BD identified in our previous study were used as target phenotypes. Associations between these phenotype dimensions and polygenic risk scores (PRSs) of major psychiatric illnesses from East Asian (EA) and other available populations were analyzed. RESULTS: Each phenotype dimension showed a different association pattern with PRSs of mental illnesses. PRS for EA schizophrenia showed a significant negative association with the cyclicity dimension (p = 0.044) but a significant positive association with the psychotic/irritable mania dimension (p = 0.001). PRS of EA major depressive disorder demonstrated a significant negative association with the elation dimension (p = 0.003) but a significant positive association with the comorbidity dimension (p = 0.028). CONCLUSION: This study demonstrates that well-defined phenotype dimensions of lifetime-basis in BD have distinct genetic risks shared with other major mental illnesses. This finding supports genetic heterogeneity in BD and suggests a pleiotropy among BD subtypes and other psychiatric disorders beyond BD. Further genomic analyses adopting deep phenotyping across mental illnesses in ancestrally diverse populations are warranted to clarify intra-diagnosis heterogeneity and inter-diagnoses commonality issues in psychiatry.
RESUMO
Exposure to solar ultraviolet (UV) radiation and use of UV-emitting tanning devices are known risk factors for skin cancer. Few studies have explored the interaction between these risk factors, namely how the risk of skin cancer increases among those who both have been exposed to high levels of natural sunlight and regularly use tanning beds. Nurses' Health Study II followed 116,430 women, aged 25-42, from 1991 to 2011. Cumulative average UV exposure was based on participants' residences at follow-up periods. History of severe sunburn during ages 15-20 was used as a proxy for early-life sunlight exposure. Tanning bed use in early life data was collected. Participants reported melanoma, basal cell carcinoma (BCC), and squamous cell carcinoma (SCC) diagnoses. We built multivariable Cox regression models to estimate hazard ratios (HRs) and 95% confidence intervals (CIs) for risk of skin cancer associated with joint effects of sunlight exposure and tanning bed use. Participants with high sunlight exposure and tanning bed use during high school/college had an increased risk of BCC (HR=1.53, CI 1.37-1.71, P interaction =0.01; vs. low UV exposure and no tanning bed use). Participants with a history of severe sunburns and tanning bed use during high school/college were at increased risk of BCC (HR=1.62, CI 1.47-1.79, P interaction =0.02; vs. no sunburns and no tanning bed use). No significant interactions were found between sunlight exposure and tanning bed use on SCC and melanoma risk. We found significant interactions between sunlight exposure and tanning bed use on the risk of BCC.
RESUMO
OBJECTIVE: To generate a Korean version of the Oxford Cognitive Screen (K-OCS) and obtain cutoff scores that determine the impairment of each subdomain. Post-stroke cognitive impairment (PSCI) negatively impacts the rehabilitation process and independence in daily life. Its obscure manifestations require effective screening for appropriate rehabilitation. However, in most rehabilitation clinics, psychological evaluation tools for Alzheimer's dementia have been used without such considerations. The OCS is a screening assessment tool for PSCI and vascular dementia that can evaluate the cognitive domains most often affected by stroke, including language, attention, memory, praxis, and numerical cognition. It comprises 10 subtasks and enables quick and effective cognitive evaluation. METHODS: The K-OCS, which considers Korea's unique cultural and linguistic characteristics, was developed with the approval and cooperation of the original author. Enrollment of participants without disabilities was announced at Duksung Women's University, Yongin Sevrance Hospital, CHA Bundang Medical Center. The study was conducted between September 2020 and March 2022 on 97 male and female participants aged ≥30 years. RESULTS: All the 97 participants completed the task. In this study, the 5th percentile score was presumed to be the cutoff value for each score, and the values are provided here. The cutoff score for each OCS subtask was similar to that of the original British version. CONCLUSION: We suggest the usability of the K-OCS as a screening tool for PSCI by providing the cutoff value of each subtask.
RESUMO
BACKGROUND: Few prospective studies exist with an evaluation of a dose-response relationship between use of some photosensitizing antihypertensive medications and skin cancer. PATIENT AND METHODS: We used prospective data from the Women's Health Initiative Observational Study to investigate the association between antihypertensive use and risk of non-melanoma skin cancer (NMSC) and melanoma in postmenopausal women aged 50-79 years at baseline (n = 64,918). Multivariable Cox proportional hazards regression models were used and hazard ratios (HRs) and 95 confidence intervals (CIs) were calculated. RESULTS: 8,777 NMSC and 1,227 melanoma cases were observed. Use of antihypertensives (HR [95% CI]: 1.12 [1.07-1.18]), ACE inhibitors (1.09 [1.01-1.18]), calcium channel blockers (1.13 [1.05-1.22]), diuretics (1.20 [1.12-1.27]), loop diuretics (1.17 [1.07-1.28]), and thiazides (1.17 [1.03-1.33]) were each associated with higher NMSC risk. NMSC risk linearly increased with use of multiple antihypertensives (p-trend = 0.02) and with longer duration of use (p-trend < 0.01). Antihypertensives (1.15 [1.00-1.31]), angiotensin-II receptor blockers (1.82 [1.05-3.15]), and diuretics (1.34 [1.13-1.59]) were each associated with elevated melanoma risk. Effect modification by solar radiation exposure was found between antihypertensive use and incidence of melanoma (p-interaction = 0.02). CONCLUSIONS: Use of antihypertensives overall, and several individual classes thereof, were associated with higher incidence of NMSC and melanoma with dose-response relationship.
Assuntos
Dermatite Fototóxica , Melanoma , Neoplasias Cutâneas , Feminino , Humanos , Anti-Hipertensivos/efeitos adversos , Melanoma/epidemiologia , Estudos Prospectivos , Pós-Menopausa , Fatores de Risco , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/epidemiologia , DiuréticosRESUMO
BACKGROUND: Frequent exposure to ultraviolet light has more detrimental and longer-term effects on the skin in early life than in adulthood. Teenagers with strong sun-seeking behaviors may be more likely to use an indoor tanning bed than those who seek less sun. We aimed to examine associations between sun-seeking behaviors and indoor tanning behavior during high school/college in US females. METHODS: In this cross-sectional study, we used data from The Nurses' Health Study II, a large prospective cohort of US female nurses. We included a total of 81,746 white females who provided responses on the average annual frequency of indoor tanning during high school/college. Our study exposures were number of times/week spent outdoors in a swimsuit and percentage of time wearing sunscreen at the pool/beach as a teenager, weekly hours spent outdoors in direct sunlight during the daytime during high school/college, and number of severe sunburns that blistered between ages 15-20 years. The main outcome was annual frequency of indoor tanning bed usage during high school/college. RESULTS: In multivariable-adjusted logistic regression, we demonstrated positive associations between sun-seeking behaviors and indoor tanning use. Specifically, teenagers who spent 7 times/week outdoors in a swimsuit (adjusted odds ratio [aOR], 95% confidence interval [CI] for daily vs. <1/week: 2.68, 1.76-4.09) were more likely to use indoor tanning beds ≥ 12 times/year. Teenagers with ≥ 10 sunburns (aOR, 95% CI for ≥ 10 vs. never: 2.18, 1.53-3.10) were more likely to use indoor tanning beds ≥ 12 times/year. Also, teenagers/undergraduates who spent ≥ 5 h/week outdoors in direct sunlight (aOR, 95% CI for ≥ 5 h/week vs. <1 h/week: 2.18, 1.39-3.44) were more likely to use indoor tanning ≥ 12 times/year. However, there was not a significant association between average usage of sunscreen at the pool/beach and average usage of indoor tanning beds. Multivariable-adjusted linear regression models also showed similar results. CONCLUSIONS: Teenagers who spent more time outdoors in a swimsuit/direct sunlight or got more sunburns tended to use indoor tanning more frequently. These findings provide evidence that teenagers with stronger sun-seeking behaviors may have more exposure to artificial ultraviolet radiation as well.
Assuntos
Enfermeiras e Enfermeiros , Neoplasias Cutâneas , Banho de Sol , Queimadura Solar , Adolescente , Humanos , Feminino , Raios Ultravioleta/efeitos adversos , Protetores Solares/uso terapêutico , Estudos Transversais , Estudos Prospectivos , Brancos , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/etiologia , Neoplasias Cutâneas/prevenção & controle , Luz Solar , Instituições Acadêmicas , Comportamentos Relacionados com a SaúdeRESUMO
BACKGROUND: Oral nicotinamide (NAM) has shown promise in preventing actinic keratoses (AKs) in trials based outside of the United States. We assessed the efficacy of oral NAM supplementation in kidney transplant recipients with a history of keratinocyte carcinoma. MATERIAL AND METHODS: Patients enrolled in a 2-week run-in phase, during which NAM 1000 mg was taken twice daily. After a washout period, patients who tolerated the run-in phase were randomized to NAM 500 mg twice daily or placebo. At baseline, 4, 8, and 12 months, dermatologists conducted full-body skin exams to document area-specific AKs. Routine lab work was collected to ensure the stability of renal allograft function. RESULTS: The dosage was reduced from 1000 to 500 mg due to gastrointestinal symptoms in the run-in phase. Patients were randomized to NAM (n = 10) or placebo (n = 11). At 12 months, mean AK count was 30.8 (95% CI -11.7-73.4) for NAM and 26.6 (95% CI 10.8-42.5) for placebo. The difference in percent AK count change at 12 months compared with baseline was 259.8% (95% CI -385.9 to 905.5) for NAM and 72.4% (95% CI -118.6 to 263.5) for placebo. The between-group difference in percent AK change was not significant (P = .38). There was no attrition in the placebo group and 40% attrition in the NAM arm. DISCUSSION: Nicotinamide did not decrease AK development among kidney transplant recipients. Limitations include drug tolerability, small sample size, and single-center trial nature.
Assuntos
Ceratose Actínica , Transplante de Rim , Humanos , Ceratose Actínica/diagnóstico , Ceratose Actínica/tratamento farmacológico , Ceratose Actínica/patologia , Niacinamida/efeitos adversos , Transplante de Rim/efeitos adversos , Resultado do Tratamento , Pele/patologia , Método Duplo-CegoRESUMO
Epidemiological studies have found that high citrus fruit consumption was associated with higher risk of skin cancer. Citrus fruits and some vegetables contain furocoumarins, which may interact with ultraviolet radiation to induce skin cancer. We aimed to determine the effects of two furocoumarins, including 8-methoxypsoralen (8-MOP) and 6',7'-dihydroxybergamottin (DHB), on UVA-induced DNA damage in human epidermal melanocytes, the origin of melanoma. Our hypothesis was that these dietary furocoumarins increase UVA-induced DNA damage in melanocytes, compared to cells exposed to UV alone. We incubated melanocytes with 8-MOP or DHB, followed by exposure to physiological doses of UVA radiation. We used Western blots to quantify the UVA-induced DNA damage measured by the fraction of phosphorylated histone variant H2AX (γH2AX), which is a marker of DNA damage, relative to total H2AX (γH2AX/H2AX) in the presence or absence of furocoumarins. To quantify the UVA-induced change in γH2AX/H2AX, we calculated the UVA:Control ratio as the ratio of γH2AX/H2AX in UVA-exposed cells to that in cells without UVA (control). The mean UVA:Control ratios were borderline significantly higher for cells treated with 8-MOP and significantly higher for cells treated with DHB, compared to that of untreated cells. This study suggests that furocoumarins (particularly 8-MOP and DHB) enhance UVA-induced DNA damage in melanocytes, which is a potential novel mechanism for citrus and furocoumarins to elevate the risk of skin cancer.
Assuntos
Citrus , Furocumarinas , Neoplasias Cutâneas , Humanos , Furocumarinas/farmacologia , Metoxaleno/farmacologia , Raios Ultravioleta/efeitos adversos , Melanócitos , Dano ao DNARESUMO
Patients with alopecia areata (AA) may experience episodic hair loss that follows seasonal patterns. To assess associations between seasonal variation, climate factors, and AA flare frequency in pediatric AA patients, we performed a retrospective chart review of 123 pediatric AA patients at Brown Dermatology (Providence, Rhode Island) who experienced hair loss between January 2017 and December 2019. We assessed association of seasonal variation with monthly occurrence of AA flares. We then assessed association between climate variables and monthly AA hair loss frequency using Spearman rank correlation analyses. We conducted stratified analyses in patients with and without history of atopy. The greatest proportion of hair loss episodes occurred in winter (28.1%), followed by autumn (26.3%), spring (23.8%), and summer (21.7%). We found significant correlations between AA hair loss frequency and air pressure (R = 0.61) and hours of sunlight (R = - 0.60). These correlations remained significant among patients with no history of atopic disease but were not significant among those with history of atopy. Limitations include small sample size. This regional analysis supports the role of climate in AA hair loss episodes through assessment of seasonal occurrences and identification of correlations between climate characteristics and AA flare frequency.
Assuntos
Alopecia em Áreas , Humanos , Criança , Alopecia em Áreas/epidemiologia , Estações do Ano , Estudos Retrospectivos , Rhode Island/epidemiologia , AlopeciaRESUMO
RATIONALE: Transnasal humidified rapid-insufflation ventilatory exchange (THRIVE) is used in tracheostomy but not in cases of airway obstruction. This case report explores the use of THRIVE for managing airway obstruction during tracheostomy in patients with subglottic and tracheal stenosis, thereby addressing the current knowledge gap and exploring its potential for airway management. PATIENT CONCERNS: A 63-year-old female with subglottic and tracheal stenoses underwent tracheostomy. Multiple attempts to establish a patent airway were unsuccessful, and oxygen saturation dropped to 56%. DIAGNOSIS: Endotracheal tube was directed toward the tracheal wall, causing airway obstruction. INTERVENTIONS: THRIVE was administered to the patient. Subsequently, the tube position was adjusted to enhance ventilation. OUTCOMES: The patient's oxygen saturation increased to 99%. The postoperative complications, including subcutaneous emphysema, pneumothorax, pneumomediastinum and pneumopericardium, resolved. The patient was discharged on postoperative day 9. LESSONS: THRIVE could be considered a temporary measure to enhance oxygenation before initiating a definitive treatment strategy.
Assuntos
Obstrução das Vias Respiratórias , Insuflação , Estenose Traqueal , Feminino , Humanos , Pessoa de Meia-Idade , Traqueostomia/efeitos adversos , Estenose Traqueal/cirurgia , Estenose Traqueal/complicações , Insuflação/efeitos adversos , Administração Intranasal , Apneia/terapia , Obstrução das Vias Respiratórias/complicaçõesRESUMO
Background: The association between statin use and risk of renal cell carcinoma (RCC) has been debated. We aimed to evaluate whether statin use is associated with RCC risk.Material and methods: We studied 100,195 women in the Nurses' Health Study (NHS) from 1994 to 2016; 91,427 women in the Nurses' Health Study II (NHS II) from 1999 to 2015; and 45,433 men in the Health Professionals Follow-up Study (HPFS) from 1990 to 2016. Statins and covariate data were collected at baseline and then biennially. Outcome was measured as incidence of total RCC and clinically relevant disease subgroups. Cox proportional hazards models estimated covariate-adjusted hazard ratios (HRs) and 95% confidence intervals (CIs).Results: During follow-up, 661 participants developed RCC. There was no significant association between the use of statins and the risk of overall RCC, fatal RCC, or advanced or localized disease. Across cohorts, the adjusted HR for ever vs. never users was 0.97 (95% CI 0.81-1.16). Female ever users of statins were at increased risk of high-grade disease in the NHS only (HR 1.75, 95% CI 1.07-2.85). Among men only, ≥4 years of statin use was associated with an increased risk of clear cell RCC (HR 1.65, 95% CI 1.10-2.47).Conclusions: Statin use was not associated with the overall risk of RCC. However, it was associated with an increased risk of high-grade disease among women in the NHS cohort and an increased risk of clear cell RCC among men. The reasons for these inconsistent results by sex are unclear.
Assuntos
Carcinoma de Células Renais , Inibidores de Hidroximetilglutaril-CoA Redutases , Neoplasias Renais , Masculino , Humanos , Feminino , Carcinoma de Células Renais/induzido quimicamente , Carcinoma de Células Renais/epidemiologia , Inibidores de Hidroximetilglutaril-CoA Redutases/efeitos adversos , Seguimentos , Estudos Prospectivos , Modelos de Riscos Proporcionais , Neoplasias Renais/induzido quimicamente , Neoplasias Renais/epidemiologia , Fatores de RiscoRESUMO
Climate change and environmental health are closely linked with agriculture and food supply. The environment influences accessibility, quality, and variety of foods and drinks that are available for consumption, which in turn influences population health. A growing area of research is the role of dietary intake of nutrients and how they may influence risk for skin cancer. In recent years, our group has studied dietary nutrients, particularly those found in commonly consumed beverages, such as those containing caffeine, citrus products, and alcohol, in large prospective cohorts to evaluate how their intake may influence risk for skin cancer. Our data suggest that intake of citrus juices, when consumed around once per day or more, or around 5 to 6 times per week, may be associated with increased risk for both keratinocyte carcinomas (KC) and malignant melanoma (MM). With regards to alcohol consumption, we have found that intake of white wine may be associated with increased risk for both KC and MM, while beer and red wine have not shown such associations. Lastly, our work suggests caffeinated beverages, including coffee, tea, and cola, may be associated with decreased risk for basal cell carcinoma (BCC) and MM. While the associations between food intake and skin cancer development are complex, and remain to be further analyzed in future studies, we hope that our summary may help guide individuals to small changes they may make towards potentially reducing their risk for certain skin cancers.
Assuntos
Citrus , Neoplasias Cutâneas , Café/efeitos adversos , Estudos Prospectivos , Neoplasias Cutâneas/epidemiologia , Neoplasias Cutâneas/etiologia , Etanol , Melanoma Maligno CutâneoRESUMO
Background: Frequent exposure to ultraviolet light in early life has more detrimental and long-term effects on skin than in adulthood. Teenagers with strong sun-seeking behaviors may be more likely to use an indoor tanning bed than those who seek less sun, probably due to addictiveness of ultraviolet exposure. We aimed to examine associations between sun exposure behaviors and average annual indoor tanning usage frequency during high school/college in US females. Methods: In this cross-sectional study, we used data from The Nurses' Health Study II, a large prospective cohort of US female nurses. We included a total of 81,746 white females who answered the average annual frequency of indoor tanning during high school/college. Our study exposures were average weekly time spent outdoors in a swimsuit and average percentage of time of wearing sunscreen at the pool or beach during their teenage years, average weekly hours spent outdoors in direct sunlight in daytime during high school/college, and the number of severe sunburns which blistered between ages 15-20. Main outcomes was average annual frequency of indoor tanning bed usage during high school/college. Results: In multivariable-adjusted logistic regression, we demonstrated positive associations between the sun exposure behaviors and the indoor tanning habit. Specifically, teenagers who spent daily outdoors in a swimsuit (adjusted odds ratio [aOR], 95% confidence interval [CI] for daily vs. <1/week: 2.68, 1.76-4.09) or who had ≥ 10 sunburns that blistered (aOR, 95% CI for ≥ 10 vs. never: 2.18, 1.53-3.10) were more likely to use indoor tanning beds ≥ 12 times/year. Also, teenagers/undergraduates who spent ≥ 5hours/week outdoors in direct sunlight during daytime used indoor tanning ≥ 12 times/year (aOR, 95% CI: 2.18, 1.39-3.44) than those who spent < 1/week. However, there was not a significant association between average uses of sunscreen at the pool/beach and indoor tanning bed. Multivariable-adjusted linear regression models also showed similar results. Conclusions: Teenagers who spent more time outdoors or got more sunburns tended to use indoor tanning more frequently. These findings provide evidence that teenagers with strong sun-seeking behaviors may have excessive exposure to artificial ultraviolet radiation as well.