Seasonality of hospital admissions and birth dates among inpatients with eating disorders: a nationwide population-based retrospective study

  • Chih-Sung Liang
  • Chi-Hsiang Chung
  • Chia-Kuang Tsai
  • Wu-Chien ChienEmail author
Original Article



Seasonal variation exists in the psychopathology of eating disorders. However, it is still unknown whether there is seasonal variation in eating disorder symptom severity. This study investigated seasonal trends in hospital admissions and birth dates among patients with eating disorders in Taiwan (25°N). Subgroup analyses by gender and comorbid affective disorders were also of interest.


Data on all hospital admissions between 2000 and 2013 were collected from the Taiwan National Health Insurance Research Database, and 1954 patients with eating disorders were identified. Hospital admissions and birth dates were recorded by day. The four seasons and cross-seasons were defined by solstices and equinoxes. The expected distribution of births was determined using data from all patients hospitalized from 2000 to 2013 (n = 13,139,306).


Hospital admissions among patients with eating disorders exceeded the rate of expected hospital admissions in the summer season (p < 0.001) and the autumn cross-season (p < 0.001). However, the seasonal (p = 0.421) and cross-seasonal (p = 0.24) distributions of birth dates among these patients did not differ from the expected distributions. Interestingly, hospital admissions among patients with comorbid affective disorders exceeded the rates of hospital admissions among non-affective patients during the spring (p = 0.004). Moreover, the number of non-affective patients born during autumn exceeded the birth rates of affective patients during this season (p = 0.001). Gender and comorbid affective disorders were not associated with cross-seasonal differences in either hospitalizations or dates of birth.


Affective psychopathology in inpatients with eating disorders may substantially contribute to symptom severity that waxes and wanes with the seasons. Moreover, the seasonal distribution of birth dates was significantly different in patients without comorbid affective disorders.


Eating disorder Seasonal variation Cross-season Affective disorder Gender Hospital admission Birth 


Compliance with ethical standards



Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

The Institutional Review Board for the Protection of Human Subjects at the Tri-Service General Hospital, a medical teaching hospital within the National Defense Medical Center in Taiwan, approved the protocol.

Informed consent

Informed consent was originally obtained by the National Health Research Institutes in Taiwan. The privacy of each individual’s information was protected using encrypted personal identification to avoid the potential for ethical violations related to the data.


  1. 1.
    Hut RA, Beersma DG (2011) Evolution of time-keeping mechanisms: early emergence and adaptation to photoperiod. Philos Trans R Soc Lond B Biol Sci 366(1574):2141–2154. doi: 10.1098/rstb.2010.0409 CrossRefPubMedPubMedCentralGoogle Scholar
  2. 2.
    Karatsoreos IN, Bhagat S, Bloss EB, Morrison JH, McEwen BS (2011) Disruption of circadian clocks has ramifications for metabolism, brain, and behavior. Proc Natl Acad Sci USA 108(4):1657–1662. doi: 10.1073/pnas.1018375108 CrossRefPubMedGoogle Scholar
  3. 3.
    Maury E, Ramsey KM, Bass J (2010) Circadian rhythms and metabolic syndrome: from experimental genetics to human disease. Circ Res 106(3):447–462. doi: 10.1161/CIRCRESAHA.109.208355 CrossRefPubMedPubMedCentralGoogle Scholar
  4. 4.
    Wulff K, Gatti S, Wettstein JG, Foster RG (2010) Sleep and circadian rhythm disruption in psychiatric and neurodegenerative disease. Nat Rev Neurosci 11(8):589–599. doi: 10.1038/nrn2868 CrossRefPubMedGoogle Scholar
  5. 5.
    Naumova EN (2006) Mystery of seasonality: getting the rhythm of nature. J Public Health Policy 27(1):2–12. doi: 10.1057/palgrave.jphp.3200061 CrossRefPubMedPubMedCentralGoogle Scholar
  6. 6.
    Dopico XC, Evangelou M, Ferreira RC, Guo H, Pekalski ML, Smyth DJ, Cooper N, Burren OS, Fulford AJ, Hennig BJ, Prentice AM, Ziegler AG, Bonifacio E, Wallace C, Todd JA (2015) Widespread seasonal gene expression reveals annual differences in human immunity and physiology. Nat Commun 6:7000. doi: 10.1038/ncomms8000 CrossRefPubMedPubMedCentralGoogle Scholar
  7. 7.
    Meyer C, Muto V, Jaspar M, Kussé C, Lambot E, Chellappa SL, Degueldre C, Balteau E, Luxen A, Middleton B, Archer SN, Collette F, Dijk D-J, Phillips C, Maquet P, Vandewalle G (2016) Seasonality in human cognitive brain responses. Proc Natl Acad Sci USA 113(11):3066–3071. doi: 10.1073/pnas.1518129113 CrossRefPubMedGoogle Scholar
  8. 8.
    Akhter A, Fiedorowicz JG, Zhang T, Potash JB, Cavanaugh J, Solomon DA, Coryell WH (2013) Seasonal variation of manic and depressive symptoms in bipolar disorder. Bipolar Disord 15(4):377–384. doi: 10.1111/bdi.12072 CrossRefPubMedPubMedCentralGoogle Scholar
  9. 9.
    Ayers JW, Althouse BM, Allem JP, Rosenquist JN, Ford DE (2013) Seasonality in seeking mental health information on Google. Am J Prev Med 44(5):520–525. doi: 10.1016/j.amepre.2013.01.012 CrossRefPubMedGoogle Scholar
  10. 10.
    Hardin TA, Wehr TA, Brewerton T, Kasper S, Berrettini W, Rabkin J, Rosenthal NE (1991) Evaluation of seasonality in six clinical populations and two normal populations. J Psychiatr Res 25(3):75–87. doi: 10.1016/0022-3956(91)90001-Q CrossRefPubMedGoogle Scholar
  11. 11.
    Brewerton TD, Krahn DD, Hardin TA, Wehr TA, Rosenthal NE (1994) Findings from the Seasonal Pattern Assessment Questionnaire in patients with eating disorders and control subjects: effects of diagnosis and location. Psychiatry Res 52(1):71–84. doi: 10.1016/0165-1781(94)90121-X CrossRefPubMedGoogle Scholar
  12. 12.
    Fornari VM, Braun DL, Sunday SR, Sandberg DE, Matthews M, Chen IL, Mandel FS, Halmi KA, Katz JL (1994) Seasonal patterns in eating disorder subgroups. Compr Psychiatry 35(6):450–456. doi: 10.1016/0010-440X(94)90228-3 CrossRefPubMedGoogle Scholar
  13. 13.
    Lam RW, Goldner EM, Grewal A (1996) Seasonality of symptoms in anorexia and bulimia nervosa. Int J Eat Disord 19(1):35–44. doi: 10.1002/(SICI)1098-108X(199601)19:1<35:AID-EAT5>3.0.CO;2-X CrossRefPubMedGoogle Scholar
  14. 14.
    Yamatsuji M, Yamashita T, Arii I, Taga C, Tatara N, Fukui K (2003) Seasonal variations in eating disorder subtypes in Japan. Int J Eat Disord 33(1):71–77. doi: 10.1002/eat.10107 CrossRefPubMedGoogle Scholar
  15. 15.
    Shuman NK, Krug I, Maxwell M, Pinheiro AP, Brewerton T, Thornton LM, Berrettini WH, Brandt H, Crawford S, Crow S, Fichter MM, Halmi KA, Johnson C, Kaplan AS, Keel P, Lavia M, Mitchell J, Rotondo A, Strober M, Woodside DB, Kaye WH, Bulik CM (2010) Is season of birth related to disordered eating and personality in women with eating disorders? Eat Weight Disord 15(3):e186–e189. doi: 10.1007/BF03325297 CrossRefPubMedPubMedCentralGoogle Scholar
  16. 16.
    Perry JA, Silvera DH, Rosenvinge JH, Neilands T, Holte A (2001) Seasonal eating patterns in Norway: a non-clinical population study. Scand J Psychol 42(4):307–312. doi: 10.1016/j.amepre.2013.01.012 CrossRefPubMedGoogle Scholar
  17. 17.
    Chotai J, Smedh K, Johansson C, Nilsson LG, Adolfsson R (2004) An epidemiological study on gender differences in self-reported seasonal changes in mood and behaviour in a general population of northern Sweden. Nord J Psychiatry 58(6):429–437. doi: 10.1080/08039480410006052 CrossRefPubMedGoogle Scholar
  18. 18.
    Winthorst WH, Roest AM, Bos EH, Meesters Y, Penninx BW, Nolen WA, de Jonge P (2014) Self-attributed seasonality of mood and behavior: a report from the Netherlands study of depression and anxiety. Depress Anxiety 31(6):517–523. doi: 10.1002/da.22130 CrossRefPubMedGoogle Scholar
  19. 19.
    Brewerton TD, Dansky BS, O’Neil PM, Kilpatrick DG (2012) Seasonal patterns of birth for subjects with bulimia nervosa, binge eating, and purging: results from the National Women’s Study. Int J Eat Disord 45(1):131–134. doi: 10.1002/eat.20898 CrossRefPubMedGoogle Scholar
  20. 20.
    Disanto G, Handel AE, Para AE, Ramagopalan SV, Handunnetthi L (2011) Season of birth and anorexia nervosa. Br J Psychiatry 198(5):404–405. doi: 10.1192/bjp.bp.110.085944 CrossRefPubMedPubMedCentralGoogle Scholar
  21. 21.
    Winje E, Torgalsboen AK, Brunborg C, Lask B (2013) Season of birth bias and anorexia nervosa: results from an international collaboration. Int J Eat Disord 46(4):340–345. doi: 10.1002/eat.22060 CrossRefPubMedGoogle Scholar
  22. 22.
    Hsing AW, Ioannidis JP (2015) Nationwide population science: lessons from the Taiwan National health insurance research database. JAMA Intern Med 175(9):1527–1529. doi: 10.1001/jamainternmed.2015.3540 CrossRefPubMedGoogle Scholar
  23. 23.
    Bou Khalil R, Hachem D, Richa S (2011) Eating disorders and schizophrenia in male patients: a review. Eat Weight Disord 16(3):e150–e156. doi: 10.1007/BF03325126 CrossRefPubMedGoogle Scholar
  24. 24.
    Brewerton TD, Berrettini WH, Nurnberger JI Jr, Linnoila M (1988) Analysis of seasonal fluctuations of CSF monoamine metabolites and neuropeptides in normal controls: findings with 5HIAA and HVA. Psychiatry Res 23(3):257–265. doi: 10.1016/0165-1781(88)90016-9 CrossRefPubMedGoogle Scholar
  25. 25.
    Quan H, Sundararajan V, Halfon P, Fong A, Burnand B, Luthi JC, Saunders LD, Beck CA, Feasby TE, Ghali WA (2005) Coding algorithms for defining comorbidities in ICD-9-CM and ICD-10 administrative data. Med Care 43(11):1130–1139. doi: 10.1097/01.mlr.0000182534.19832.83 CrossRefGoogle Scholar
  26. 26.
    Hoek HW, van Hoeken D (2003) Review of the prevalence and incidence of eating disorders. Int J Eat Disord 34(4):383–396. doi: 10.1002/eat.10222 CrossRefPubMedGoogle Scholar
  27. 27.
    Magnusson A (2000) An overview of epidemiological studies on seasonal affective disorder. Acta Psychiatr Scand 101(3):176–184. doi: 10.1034/j.1600-0447.2000.101003176.x CrossRefPubMedGoogle Scholar
  28. 28.
    Ghadirian AM, Marini N, Jabalpurwala S, Steiger H (1999) Seasonal mood patterns in eating disorders. Gen Hosp Psychiatry 21(5):354–359. doi: 10.1016/S0163-8343(99)00028-6 CrossRefPubMedGoogle Scholar
  29. 29.
    Rutter M (2005) How the environment affects mental health. Br J Psychiatry 186:4–6. doi: 10.1192/bjp.186.1.4 CrossRefPubMedGoogle Scholar
  30. 30.
    Foster RG, Roenneberg T (2008) Human responses to the geophysical daily, annual and lunar cycles. Curr Biol 18(17):R784–R794. doi: 10.1016/j.cub.2008.07.003 CrossRefPubMedGoogle Scholar
  31. 31.
    Ciarleglio CM, Axley JC, Strauss BR, Gamble KL, McMahon DG (2011) Perinatal photoperiod imprints the circadian clock. Nat Neurosci 14(1):25–27. doi: 10.1038/nn.2699 CrossRefPubMedGoogle Scholar
  32. 32.
    Winje E, Willoughby K, Lask B (2008) Season of birth bias in eating disorders–fact or fiction? Int J Eat Disord 41(6):479–490. doi: 10.1002/eat.20540 CrossRefPubMedGoogle Scholar
  33. 33.
    Pjrek E, Winkler D, Heiden A, Praschak-Rieder N, Willeit M, Konstantinidis A, Stastny J, Kasper S (2004) Seasonality of birth in seasonal affective disorder. J Clin Psychiatry 65(10):1389–1393. doi: 10.4088/JCP.v65n1014 CrossRefPubMedGoogle Scholar

Copyright information

© Springer International Publishing Switzerland 2016

Authors and Affiliations

  • Chih-Sung Liang
    • 1
    • 2
  • Chi-Hsiang Chung
    • 3
    • 4
  • Chia-Kuang Tsai
    • 2
    • 5
  • Wu-Chien Chien
    • 3
    • 6
    Email author
  1. 1.Department of Psychiatry, Beitou Branch, Tri-Service General HospitalNational Defense Medical CenterTaipeiTaiwan, ROC
  2. 2.Graduate Institute of Medical SciencesNational Defense Medical CenterTaipeiTaiwan, ROC
  3. 3.School of Public HealthNational Defense Medical CenterTaipeiTaiwan, ROC
  4. 4.Taiwanese Injury Prevention and Safety Promotion AssociationTaipeiTaiwan, ROC
  5. 5.Department of Neurology, Tri-Service General HospitalNational Defense Medical CenterTaipeiTaiwan, ROC
  6. 6.Department of Medical Research, Tri-Service General HospitalNational Defense Medical CenterTaipeiTaiwan, ROC

Personalised recommendations