Factors Impacting Quality of Life in Patients With Klinefelter Syndrome: A Systematic Review with Narrative Synthesis and Meta-Analysis

Objective: To identify how Klinefelter’s Syndrome affects patients’ quality of life (QoL) and to determine which subsections of QoL are affected guided by the WHOQOL100-tool as an overarching framework for QoL. To determine the effects and impact KS has on patients’ QoL when compared to the QoL of healthy controls and general population. DESIGN - Systematic review of studies reporting QoL factors among patients with KS which included narrative synthesis and thematic analysis of 17 studies and a meta-analysis of intelligence quotient (IQ) completed in 7 studies. QoL factors were reviewed based on the parameters of the WHOQOL-100: physical health, psychological, level of independence, social relations, environment, and religion/spirituality/personal beliefs. DATA SOURCES - Medline, Cochrane, Embase, Psychinfo, CINAHL, BASE and grey search from the reference lists of key publications. Eligibility Criteria: RCT’s, Cohort studies, cross sectional studies and Epidemiology studies involving patients with KS and reporting on QoL parameters. Only human studies published in English were considered with no limits for publication date. Results: Out of all studies included (n=1266), (87.5%) had suggested KS negatively affected the outcomes measures tested, where recorded (91.1%) of studies had small/medium/large effect sizes (Cohen’s d). Narrative synthesis suggests all subgroups of QoL excluding ‘environment’ and ‘spirituality/faith/personal beliefs’ were negatively impacted for patients with KS, whilst meta-analysis showed statistical significance (P <0.00001) which identified patients with KS having lower full-scale IQ compared to healthy controls. Psychological parameters were the most affected in this patient group, showing that patients with KS experienced greater social anxiety, distress during social interactions, self-esteem, self-injuries behaviours and symptoms or traits related to Autism spectrum. Conclusions: This review identifies the significant evidence supporting that QoL is reduced in patients with KS. There is a large spectrum of symptoms and no standard phenotype for KS suggesting that multiple facets of QoL are negatively impacted in these patients due to the complex nature of KS and the severity of symptoms and phenotype associated with KS. PROSPERO REGISTRATION NUMBER - CRD4202017343