This study is the first to assess SASS and UCLA-LS scales in adult PID patients, exploring their connections with HADS-A/HADS-D. Our findings revealed impaired social functioning, loneliness, and depressive symptoms in adult PID patients. Additionally, social maladjustment, anxiety, depression, and loneliness exhibited positive correlations within this population. All variables of interest were adversely affected in those who had applied for a disability report or had low income. Risk factors for loneliness included a family history of PID, comorbidities, prolonged hospital stay, dissatisfaction with IgRT, and living in a village or small town, while anxiety risk factors comprised residing outside the city and being younger at symptom onset and PID diagnosis. Depression risk factors involved prolonged hospital stay and dissatisfaction with IgRT.

Our study determined the risk of anxiety disorder as 44.2% and the risk of depression as 61.5% based on HADS-A and HADS-D scores; this aligns with trends observed in other studies using the Hamilton Anxiety Rating Scale [20]. Similarly, in a study where depression and anxiety risk were assessed in 96 patients diagnosed with common variable immunodeficiency using a variety of scales, including a generic, non-disease-specific instrument (SF-36) and the General Health Questionnaire (GHQ-12), approximately one-third of the patients were identified to be at risk of anxiety and depression during the observation period [11]. This finding suggests a consistent psychiatric profile among PID patients, despite the use of different measurement scales. Additionally, in a study with PID-diagnosed children, 70.45% exhibited psychiatric problems, with depression (27.3%), disruptive behavior disorders (27.3%), and anxiety disorders (18.2%) being the most prevalent diagnoses [21]. Another pediatric study indicated that clinically significant anxiety or depressive symptoms were observed in almost one out of every 4–5 children with PID [10]. As a result, anxiety and depression symptoms appear to be significantly high in PID patients, independent of screening tools and age groups. However, as observed in our study and many others, self-report measurements are commonly used instead of structured clinical interviews and criteria for anxiety and depressive disorders. This tendency may lead to higher prevalence estimates than those reported in studies involving clinical reassessments [22]. For these reasons, following the confirmation of PID diagnosis, it is recommended that instead of initiating anxiety and depression risk screening, patients undergo a psychiatric evaluation by a mental health specialist. This approach allows for early psychiatric monitoring and treatment initiation. However, its practicality and feasibility may pose challenges. Therefore, for a more comprehensive understanding and the development of strategies, further studies are needed, not only in the context of PID patients but also across chronic diseases in general.

Adults with immunodeficiency cannot work in physically demanding jobs or crowded environments and are often not preferred by employers due to their illness. Working patients, on the other hand, may have difficulty in taking leave for treatment and follow-up, and constantly feel the pressure of possibly being fired due to frequent hospital admissions. Despite the generally high educational levels among our patients (2.9% with no education or illiteracy, and 51% being university graduates), the 43.3% unemployment rate can be partially considered a result of this situation. Moreover, essential needs such as medication, medical examinations, and hospital transportation expenses can create a significant financial burden, contributing to the disruption of the balance between income and expenses, as observed in our patients.

In our study, patients who lived outside urban areas felt lonelier and more anxious. This finding is likely because cities offer better access to health care and more job and social opportunities. However, the cost of living is higher in cities than in rural areas. Moreover, we noted that patients using public transportation had poorer social functioning in our study group. When we investigated the characteristics of this subset of patients, we determined that most of them reported low income. In this study, the common problems of anxiety, depression, loneliness, and poor social functioning in PID patients seem to be related to financial distress. The literature confirms that individuals with chronic diseases and low socioeconomic status are at greater risk of limitation, dependency, social isolation, psychological distress, and impaired quality of life [16]. Living with PID in middle- and low-income countries is much more difficult and can lead to life-threatening problems. In our country, a disability health board report is required in order to benefit from the financial and social assistance provided by the state and private sector to disabled persons [23]. In our sample, 48.5% of the patients had applied for this report and 62% of those who applied were approved (30% of all patients). However, this assistance should be expanded to cover basic needs, medical costs, and social needs for PID patients. In addition, introducing new criteria for disability reports for PID patients or making the process of getting the report easier should be considered.

In recent years, it has been clearly seen that switching to at-home SCIG treatment instead of hospital-based IVIG has increased the quality of life [24, 25]. In our patients, rates of satisfaction with IGRT were found to be highest in those receiving IVIG (88%), followed by SCIG (76.2%) and fSCIG (66.7%), with no significant difference in satisfaction between the different infusion methods. This result may be because all infusion options are evaluated jointly with the patients in our clinic. Treatment is selected according to the patients’ needs and conditions and subsequently revised according to their satisfaction and compliance with the treatment. Despite this, 15% of our patients were not satisfied with IGRT, and symptoms of depression and loneliness were more common in these patients. Moreover, we observed in this study that younger age at diagnosis and symptom onset were associated with higher anxiety, while anxiety, loneliness, and depression increased with longer hospital stays. When our patients were evaluated overall, their disease and treatment history significantly affected their psychosocial status. Different studies investigating different parameters have demonstrated a relationship between depression and severe disease, frequent hospital admissions, a high number of complications, a high number of annual infections, not being able to come to the hospital by car, IVIG (vs. SCIG) treatment, nurse-administered treatment (vs. self-administered), contralateral side effects of IGRT, and suicide attempts. On the other hand, poor health status, unhealthy diet, and lack of restful sleep were reported as risk factors for anxiety [21, 26]. In addition, delay in diagnosis for more than six years and the presence of a family history of anxiety and/or depression have been shown to have a significant effect on both anxiety and depression scores [20, 26].

Franco et al. conducted a behavioral and neuroanatomical evaluation of the effects of loneliness and social adjustment on depressive symptoms. They showed that loneliness enhances depressive symptoms but has a positive effect on social functioning. Additionally, loneliness, social functioning, and depressive symptoms share a common white matter area in the brain [27]. A five-year longitudinal study provided evidence of a unilateral relationship in which loneliness predicted, if not promoted, increases in depressive symptomatology in middle-aged and older adults. The authors also noted that this temporal relationship could not be attributed to demographic variables, objective social isolation, temperamental negativity, stress, or social support [12]. However, in a longitudinal cohort study including older adults, loneliness was an important predictor for depression but showed no significant association with anxiety [13]. In addition, Saris et al. suggested that social disability acted as a predictor of anxiety and/or depressive disorders (8). In the current study, social maladjustment, anxiety, depression, and loneliness were found to correlate with each other. However, since our study was cross-sectional, we cannot determine the causality of these relationships.

In conclusion, social dysfunction, loneliness, anxiety, and depression are common in adults with PID. The results of this study highlight the need to evaluate these patients in terms of their psychiatric, social, and economic needs with an interdisciplinary team including clinicians, social workers, and psychiatrists.