PPD occurs in 6% to 20% of psychiatric patients, and is most commonly seen in people with schizophrenia.[4]Jose CJ, Perez-Cruet J. Incidence and morbidity of self-induced water intoxication in state mental hospital patients. Am J Psychiatry. 1979 Feb;136(2):221-2.
http://www.ncbi.nlm.nih.gov/pubmed/760555?tool=bestpractice.com
[5]Blum A, Tempey FW, Lynch WJ. Somatic findings in patients with psychogenic polydipsia. J Clin Psychiatry. 1983 Feb;44(2):55-6.
http://www.ncbi.nlm.nih.gov/pubmed/6826531?tool=bestpractice.com
[6]Meulendijks D, Mannesse CK, Jansen PA, et al. Antipsychotic-induced hyponatraemia: a systematic review of the published evidence. Drug Saf. 2010 Feb 1;33(2):101-14.
http://www.ncbi.nlm.nih.gov/pubmed/20082537?tool=bestpractice.com
[7]Mannesse CK, van Puijenbroek EP, Jansen PA, et al. Hyponatraemia as an adverse drug reaction of antipsychotic drugs: a case-control study in VigiBase. Drug Saf. 2010 Jul 1;33(7):569-78.
http://www.ncbi.nlm.nih.gov/pubmed/20553058?tool=bestpractice.com
It may also present in people with other psychiatric disorders and neurodevelopmental disorders.[1]Verghese C, De Leon J, Josiassen RC. Problems and progress in the diagnosis and treatment of polydipsia and hyponatremia. Schizophr Bull. 1996;22(3):455-64.
https://academic.oup.com/schizophreniabulletin/article/22/3/455/1829836
http://www.ncbi.nlm.nih.gov/pubmed/8873296?tool=bestpractice.com
[2]de Leon J. Polydipsia: a study in a long-term psychiatric unit. Eur Arch Psychiatry Clin Neurosci. 2003 Feb;253(1):37-9.
http://www.ncbi.nlm.nih.gov/pubmed/12664312?tool=bestpractice.com
[3]Illowsky BP, Kirch DG. Polydipsia and hyponatremia in psychiatric patients. Am J Psychiatry. 1988 Jun;145(6):675-83.
http://www.ncbi.nlm.nih.gov/pubmed/3285701?tool=bestpractice.com
Overall, PPD is observed in 10% to 20% of patients with schizophrenia, but PPD with symptomatic hyponatraemia occurs in only 3% to 6% of these patients.[10]Ahmadi L, Goldman MB. Primary polydipsia: update. Best Pract Res Clin Endocrinol Metab. 2020 Sep;34(5):101469.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7683824
http://www.ncbi.nlm.nih.gov/pubmed/33222764?tool=bestpractice.com
[12]Gleadhill IC, Smith TA, Yium JJ. Hyponatremia in patients with schizophrenia. South Med J. 1982 Apr;75(4):426-8.
http://www.ncbi.nlm.nih.gov/pubmed/6122272?tool=bestpractice.com
Affective disorders, anxiety disorder, anorexia nervosa, obsessive compulsive disorder, and personality disorders have all been associated with PPD. PPD seen in adolescents and young adults is often associated with anorexia nervosa, possibly as a coping strategy and/or to reduce hunger.[13]Torosyan N, Spencer D, Penev S, et al. Psychogenic polydipsia in a woman with anorexia nervosa: case report and recommendations. Prim Care Companion CNS Disord. 2018 Feb 8;20(1):17l02120.
https://www.psychiatrist.com/pcc/psychiatry/psychogenic-polydipsia-in-anorexia
http://www.ncbi.nlm.nih.gov/pubmed/29490124?tool=bestpractice.com
[14]Nauwynck E, Van De Maele K, Vanbesien J, et al. Psychogenic polydipsia in a female adolescent without a psychiatric background: a case report. Clin Case Rep. 2021 Apr;9(4):1937-42.
https://onlinelibrary.wiley.com/doi/10.1002/ccr3.3910
http://www.ncbi.nlm.nih.gov/pubmed/33936619?tool=bestpractice.com
PPD has also been noted in people with neurodevelopmental disorders, including autism spectrum disorder and Kleine-Levin syndrome. Prevalence was 3.5% in a survey of 877 inpatients with diagnoses including autism and personality/behaviour disorders.[15]Bremner AJ, Regan A. Intoxicated by water: polydipsia and water intoxication in a mental handicap hospital. Br J Psychiatry. 1991 Feb;158:244-50.
http://www.ncbi.nlm.nih.gov/pubmed/2012917?tool=bestpractice.com
Another study, in a hospital population of 371 patients with developmental disabilities, found a prevalence of 6.2%.[16]Deb S, Bramble D, Drybala G, et al. Polydipsia amongst adults with a learning disability in an institution. J Intellect Disabil Res. 1994 Aug;38 ( Pt 4):359-67.
http://www.ncbi.nlm.nih.gov/pubmed/7949788?tool=bestpractice.com
Increasing popularity of lifestyle programmes that advocate water drinking to improve overall health have led to a rise in polydipsia among the general population.[10]Ahmadi L, Goldman MB. Primary polydipsia: update. Best Pract Res Clin Endocrinol Metab. 2020 Sep;34(5):101469.
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7683824
http://www.ncbi.nlm.nih.gov/pubmed/33222764?tool=bestpractice.com