Remission, complications, and overall survival in transsphenoidal pituitary surgery-a Swedish single-center experience of 578 patients.

BACKGROUND: Surgical treatment of pituitary lesions causing hormonal overproduction or mass effect is standard procedure. There are few reports on the results and complications related to these surgeries from Northern Europe. Our aim was to evaluate the outcome and complications of a single tertiary surgical center over more than a decade. METHODS: This was a retrospective study on all patients that underwent pituitary surgery from 1st of January 2005 to 31st of December 2017. The analysis included type of lesion, surgical method, pre- and postoperative need for hormonal substitution, hormonal outcome, complications to surgery, survival, need for revision surgery, or stereotactic radiation. Appropriate statistical analyses were made to evaluate surgical results, complications, and survival. RESULTS: Five hundred seventy-eight patients were included in the study. Remission was achieved in 58% of patients with GH-producing and 94% of ACTH-releasing adenomas. Sixty-six percent had no preoperative hormonal substitution compared to 39% postoperatively. Rhinosinusitis (10%) was the most commonly reported postoperative complication followed by leakage of cerebrospinal fluid (8%) and meningitis (4%). Standardized mortality rate for the study population was higher (p = 0.18) when compared to the general population. CONCLUSION: Our results regarding remission rates and complications are in comparison with previous studies. Surgery of pituitary lesion can be considered a safe and efficient surgery. We noted lower rates of CSF leakage in the later part of the study period and believe that this, in part, was an effect by the introduction of a multidisciplinary surgical skull base team and increased surgical experience.

GWAS for autoimmune Addison's disease identifies multiple risk loci and highlights AIRE in disease susceptibility.

Autoimmune Addison's disease (AAD) is characterized by the autoimmune destruction of the adrenal cortex. Low prevalence and complex inheritance have long hindered successful genetic studies. We here report the first genome-wide association study on AAD, which identifies nine independent risk loci (P < 5 × 10-8). In addition to loci implicated in lymphocyte function and development shared with other autoimmune diseases such as HLA, BACH2, PTPN22 and CTLA4, we associate two protein-coding alterations in Autoimmune Regulator (AIRE) with AAD. The strongest, p.R471C (rs74203920, OR = 3.4 (2.7-4.3), P = 9.0 × 10-25) introduces an additional cysteine residue in the zinc-finger motif of the second PHD domain of the AIRE protein. This unbiased elucidation of the genetic contribution to development of AAD points to the importance of central immunological tolerance, and explains 35-41% of heritability (h2).

Evaluation of different hydrocortisone treatment strategies in transsphenoidal pituitary surgery.

BACKGROUND: Hydrocortisone treatment in transsphenoidal pituitary surgery has been debated. Although several publications advocate restrictive treatment, centers around the world administer stress doses of hydrocortisone in patients with presumed intact cortisol production. Our aim with this analysis was to compare postoperative hypocortisolism in patients who received three different protocols of hydrocortisone therapy during and after surgery. METHOD: This was a retrospective observational study. Based on perioperative hydrocortisone dose given, patients were divided in three groups: high dose (HD), intermediate dose (ID), and low dose (LD). Postoperative evaluation of the pituitary function was performed using S-cortisol at day 4 and short Synacthen test (SST) at 6-8 weeks. Patients with ACTH-producing adenomas or preoperative hydrocortisone treatment were excluded. RESULT: There was no difference between the groups regarding failure rate of SST. The rate of failed SST (all groups) was 51/186 (27%), 24/74 (32%) in the HD group and 26/74 (35%) and 11/38 (29%) in the ID and LD groups respectively. There was no significant difference between the ID and LD groups regarding S-cortisol at postoperative day 4 regarding serum cortisol level below 200 nmol/L. There was a significant but weak correlation, rs 0.330 (P < 0.01) between S-cortisol day 4 and SST at 4-6 weeks. CONCLUSIONS: Peri and postoperative hydrocortisone treatment did not affect SST response 6-8 weeks postoperatively, whereas the rate of patients with S-cortisol below 200 nmol/L at postoperative day 4 did. LD hydrocortisone therapy seems to favor a better endogenous production in the early postoperative phase.

Common genetic variation in the autoimmune regulator (AIRE) locus is associated with autoimmune Addison's disease in Sweden.

Autoimmune Addison's disease (AAD) is the predominating cause of primary adrenal failure. Despite its high heritability, the rarity of disease has long made candidate-gene studies the only feasible methodology for genetic studies. Here we conducted a comprehensive reinvestigation of suggested AAD risk loci and more than 1800 candidate genes with associated regulatory elements in 479 patients with AAD and 2394 controls. Our analysis enabled us to replicate many risk variants, but several other previously suggested risk variants failed confirmation. By exploring the full set of 1800 candidate genes, we further identified common variation in the autoimmune regulator (AIRE) as a novel risk locus associated to sporadic AAD in our study. Our findings not only confirm that multiple loci are associated with disease risk, but also show to what extent the multiple risk loci jointly associate to AAD. In total, risk loci discovered to date only explain about 7% of variance in liability to AAD in our study population.

Cytokine Autoantibody Screening in the Swedish Addison Registry Identifies Patients With Undiagnosed APS1.

Context: Autoimmune polyendocrine syndrome type 1 (APS1) is a monogenic disorder that features autoimmune Addison disease as a major component. Although APS1 accounts for only a small fraction of all patients with Addison disease, early identification of these individuals is vital to prevent the potentially lethal complications of APS1. Objective: To determine whether available serological and genetic markers are valuable screening tools for the identification of APS1 among patients diagnosed with Addison disease. Design: We systematically screened 677 patients with Addison disease enrolled in the Swedish Addison Registry for autoantibodies against interleukin-22 and interferon-α4. Autoantibody-positive patients were investigated for clinical manifestations of APS1, additional APS1-specific autoantibodies, and DNA sequence and copy number variations of AIRE. Results: In total, 17 patients (2.5%) displayed autoantibodies against interleukin-22 and/or interferon-α4, of which nine were known APS1 cases. Four patients previously undiagnosed with APS1 fulfilled clinical, genetic, and serological criteria. Hence, we identified four patients with undiagnosed APS1 with this screening procedure. Conclusion: We propose that patients with Addison disease should be routinely screened for cytokine autoantibodies. Clinical or serological support for APS1 should warrant DNA sequencing and copy number analysis of AIRE to enable early diagnosis and prevention of lethal complications.

Acromegaly at diagnosis in 3173 patients from the Liège Acromegaly Survey (LAS) Database.

Acromegaly is a rare disorder caused by chronic growth hormone (GH) hypersecretion. While diagnostic and therapeutic methods have advanced, little information exists on trends in acromegaly characteristics over time. The Liège Acromegaly Survey (LAS) Database, a relational database, is designed to assess the profile of acromegaly patients at diagnosis and during long-term follow-up at multiple treatment centers. The following results were obtained at diagnosis. The study population consisted of 3173 acromegaly patients from ten countries; 54.5% were female. Males were significantly younger at diagnosis than females (43.5 vs 46.4 years; P < 0.001). The median delay from first symptoms to diagnosis was 2 years longer in females (P = 0.015). Ages at diagnosis and first symptoms increased significantly over time (P < 0.001). Tumors were larger in males than females (P < 0.001); tumor size and invasion were inversely related to patient age (P < 0.001). Random GH at diagnosis correlated with nadir GH levels during OGTT (P < 0.001). GH was inversely related to age in both sexes (P < 0.001). Diabetes mellitus was present in 27.5%, hypertension in 28.8%, sleep apnea syndrome in 25.5% and cardiac hypertrophy in 15.5%. Serious cardiovascular outcomes like stroke, heart failure and myocardial infarction were present in <5% at diagnosis. Erythrocyte levels were increased and correlated with IGF-1 values. Thyroid nodules were frequent (34.0%); 820 patients had colonoscopy at diagnosis and 13% had polyps. Osteoporosis was present at diagnosis in 12.3% and 0.6-4.4% had experienced a fracture. In conclusion, this study of >3100 patients is the largest international acromegaly database and shows clinically relevant trends in the characteristics of acromegaly at diagnosis.

Clinical and Immunological Characteristics of Autoimmune Addison Disease: A Nationwide Swedish Multicenter Study.

Context: Studies of the clinical and immunological features of autoimmune Addison disease (AAD) are needed to understand the disease burden and increased mortality. Objective: To provide upgraded data on autoimmune comorbidities, replacement therapy, autoantibody profiles, and cardiovascular risk factors. Design, Setting, and Participants: A cross-sectional, population-based study that included 660 AAD patients from the Swedish Addison Registry (2008-2014). When analyzing the cardiovascular risk factors, 3594 individuals from the population-based survey in Northern Sweden, MONICA (monitoring of trends and determinants of cardiovascular disease), served as controls. Main Outcome Measures: The endpoints were the prevalence of autoimmune comorbidities and cardiovascular risk factors. Autoantibodies against 13 autoantigens were determined. Results: The proportion of 21-hydroxylase autoantibody-positive patients was 83%, and 62% of patients had ≥1 associated autoimmune diseases, more frequently coexisting in females (P < 0.0001). AAD patients had a lower body mass index (P < 0.0001) and prevalence of hypertension (P = 0.027) compared with controls. Conventional hydrocortisone tablets were used by 89% of the patients, with a mean dose of 28.1 ± 8.5 mg/d. The mean hydrocortisone equivalent dose normalized to the body surface was 14.8 ± 4.4 mg/m2/d. A greater hydrocortisone equivalent dose was associated with a greater incidence of hypertension (P = 0.046). Conclusions: Careful monitoring of AAD patients is warranted to detect associated autoimmune diseases. Contemporary Swedish AAD patients did not have an increased prevalence of overweight, hypertension, type 2 diabetes mellitus, or hyperlipidemia. However, high glucocorticoid replacement doses could be a risk factor for hypertension.

MANAGEMENT OF ENDOCRINE DISEASE: Epidemiology, quality of life and complications of primary adrenal insufficiency: a review.

In this article, we review published studies covering epidemiology, natural course and mortality in primary adrenal insufficiency (PAI) or Addison's disease. Autoimmune PAI is a rare disease with a prevalence of 100-220 per million inhabitants. It occurs as part of an autoimmune polyendocrine syndrome in more than half of the cases. The patients experience impaired quality of life, reduced parity and increased risk of preterm delivery. Following a conventional glucocorticoid replacement regimen leads to a reduction in bone mineral density and an increase in the prevalence of fractures. Registry studies indicate increased mortality, especially evident in patients diagnosed with PAI at a young age and in patients with the rare disease autoimmune polyendocrine syndrome type-1. Most notably, unnecessary deaths still occur because of adrenal crises. All these data imply the need to improve the therapy and care of patients with PAI.

Circadian hormone profiles and insulin sensitivity in patients with Addison's disease: a comparison of continuous subcutaneous hydrocortisone infusion with conventional glucocorticoid replacement therapy.

CONTEXT: Conventional glucocorticoid replacement therapy in patients with Addison's disease (AD) is unphysiological with possible adverse effects on mortality, morbidity and quality of life. The diurnal cortisol profile can likely be restored by continuous subcutaneous hydrocortisone infusion (CSHI). OBJECTIVE: The aim of this study was to compare circadian hormone rhythms and insulin sensitivity in conventional thrice-daily regimen of glucocorticoid replacement therapy with CSHI treatment in patients with AD. DESIGN AND SETTING: An open, randomized, two-period, 12-week crossover multicentre trial in Norway and Sweden. PATIENTS: Ten Norwegian patients were admitted for 24-h sampling of hormone profiles. Fifteen Swedish patients underwent euglycaemic-hyperinsulinaemic clamp. INTERVENTION: Thrice-daily regimen of oral hydrocortisone (OHC) and CSHI treatment. MAIN OUTCOME MEASURE: We measured the circadian rhythm of cortisol, adrenocorticotropic hormone (ACTH), growth hormone (GH), insulin-like growth factor-1, (IGF-1), IGF-binding protein-3 (IGFBP-3), glucose, insulin and triglycerides during OHC and CSHI treatment. Euglycaemic-hyperinsulinaemic clamp was used to assess insulin sensitivity. RESULTS: Continuous subcutaneous hydrocortisone infusion provided a more physiological circadian cortisol curve including a late-night cortisol surge. ACTH levels showed a near normal circadian variation for CSHI. CSHI prevented a continuous decrease in glucose during the night. No difference in insulin sensitivity was observed between the two treatment arms. CONCLUSION: Continuous subcutaneous hydrocortisone infusion replacement re-established a circadian cortisol rhythm and normalized the ACTH levels. Patients with CSHI replacement had a more stable night-time glucose level compared with OHC without compromising insulin sensitivity. Thus, restoring night-time cortisol levels might be advantageous for patients with AD.

Association of autoimmune Addison's disease with alleles of STAT4 and GATA3 in European cohorts.

BACKGROUND: Gene variants known to contribute to Autoimmune Addison's disease (AAD) susceptibility include those at the MHC, MICA, CIITA, CTLA4, PTPN22, CYP27B1, NLRP-1 and CD274 loci. The majority of the genetic component to disease susceptibility has yet to be accounted for. AIM: To investigate the role of 19 candidate genes in AAD susceptibility in six European case-control cohorts. METHODS: A sequential association study design was employed with genotyping using Sequenom iPlex technology. In phase one, 85 SNPs in 19 genes were genotyped in UK and Norwegian AAD cohorts (691 AAD, 715 controls). In phase two, 21 SNPs in 11 genes were genotyped in German, Swedish, Italian and Polish cohorts (1264 AAD, 1221 controls). In phase three, to explore association of GATA3 polymorphisms with AAD and to determine if this association extended to other autoimmune conditions, 15 SNPs in GATA3 were studied in UK and Norwegian AAD cohorts, 1195 type 1 diabetes patients from Norway, 650 rheumatoid arthritis patients from New Zealand and in 283 UK Graves' disease patients. Meta-analysis was used to compare genotype frequencies between the participating centres, allowing for heterogeneity. RESULTS: We report significant association with alleles of two STAT4 markers in AAD cohorts (rs4274624: P = 0.00016; rs10931481: P = 0.0007). In addition, nominal association of AAD with alleles at GATA3 was found in 3 patient cohorts and supported by meta-analysis. Association of AAD with CYP27B1 alleles was also confirmed, which replicates previous published data. Finally, nominal association was found at SNPs in both the NF-κB1 and IL23A genes in the UK and Italian cohorts respectively. CONCLUSIONS: Variants in the STAT4 gene, previously associated with other autoimmune conditions, confer susceptibility to AAD. Additionally, we report association of GATA3 variants with AAD: this adds to the recent report of association of GATA3 variants with rheumatoid arthritis.

Continuous subcutaneous hydrocortisone infusion versus oral hydrocortisone replacement for treatment of addison's disease: a randomized clinical trial.

CONTEXT: Conventional glucocorticoid replacement therapy fails to mimic the physiological cortisol rhythm, which may have implications for morbidity and mortality in patients with Addison's disease. OBJECTIVE: The objective of the study was to compare the effects of continuous sc hydrocortisone infusion (CSHI) with conventional oral hydrocortisone (OHC) replacement therapy. DESIGN, PATIENTS, AND INTERVENTIONS: This was a prospective crossover, randomized, multicenter clinical trial comparing 3 months of treatment with thrice-daily OHC vs CSHI. From Norway and Sweden, 33 patients were enrolled from registries and clinics. All patients were assessed at baseline and after 8 and 12 weeks in each treatment arm. MAIN OUTCOME MEASURES: The morning ACTH level was the primary outcome measure. Secondary outcome measures were effects on metabolism, health-related quality of life (HRQoL), sleep, and safety. RESULTS: CSHI yielded normalization of morning ACTH and cortisol levels, and 24-hour salivary cortisol curves resembled the normal circadian variation. Urinary concentrations of glucocorticoid metabolites displayed a normal pattern with CSHI but were clearly altered with OHC. Several HRQoL indices in the vitality domain improved over time with CSHI. No benefit was found for either treatments for any subjective (Pittsburgh Sleep Quality Index questionnaire) or objective (actigraphy) sleep parameters. CONCLUSION: CSHI safely brought ACTH and cortisol toward normal circadian levels without adversely affecting glucocorticoid metabolism in the way that OHC did. Positive effects on HRQoL were noted with CSHI, indicating that physiological glucocorticoid replacement therapy may be beneficial and that CSHI might become a treatment option for patients poorly controlled on conventional therapy.

Galanin and its three receptors in human pituitary adenoma.

Galanin, a 29-aminoacid peptide (30 in humans), is widely distributed in the nervous and endocrine systems and exerts its actions via three G-protein-coupled receptors, GalR1-3. The galanin system has, among others, been associated with tumorigenesis. Our objective was to assess the expression of galanin and its receptors in pituitary tumors. Transcript levels of galanin and galanin receptors 1-3 (GalR1-3) were measured using quantitative real-time PCR (q-PCR) in pituitary tumors, surgically removed from thirteen patients, and twelve post mortem pituitaries. Galanin, GalR1 and GalR2 mRNA, but not GalR3 mRNA, were found in the twelve human post-mortem pituitaries. Expression of GalR1 was relatively increased in most, whereas GalR2 was decreased in some tumors. High levels of GalR3 were only found in tumors of five patients, who all relapsed shortly after surgical intervention. The results suggest that GalR3, a receptor for the neuroendocrine peptide galanin, is a potential marker for relapsing pituitary tumors. Thus, galanin receptors may play an important role in pituitary tumors, also for surgical outcome and prognosis, and may serve as a diagnostic tool. The association of GalR3 with tumor relapse suggests that antagonists to this receptor represent a potential therapeutic approach to treatment of pituitary tumors.

Quality of life in European patients with Addison's disease: validity of the disease-specific questionnaire AddiQoL.

CONTEXT: Patients with Addison's disease (AD) self-report impairment in specific dimensions on well-being questionnaires. An AD-specific quality-of-life questionnaire (AddiQoL) was developed to aid evaluation of patients. OBJECTIVE: We aimed to translate and determine construct validity, reliability, and concurrent validity of the AddiQoL questionnaire. METHODS: After translation, the final versions were tested in AD patients from Norway (n = 107), Sweden (n = 101), Italy (n = 165), Germany (n = 200), and Poland (n = 50). Construct validity was examined by exploratory factor analysis and Rasch analysis, aiming at unidimensionality and fit to the Rasch model. Reliability was determined by Cronbach's coefficient-α and Person separation index. Longitudinal reliability was tested by differential item functioning in stable patient subgroups. Concurrent validity was examined in Norwegian (n = 101) and Swedish (n = 107) patients. RESULTS: Exploratory factor analysis and Rasch analysis identified six items with poor psychometric properties. The 30 remaining items fitted the Rasch model and proved unidimensional, supported by appropriate item and person fit residuals and a nonsignificant χ(2) probability. Crohnbach's α-coefficient 0.93 and Person separation index 0.86 indicate high reliability. Longitudinal reliability was excellent. Correlation with Short Form-36 and Psychological General Well-Being Index scores was high. A shorter subscale comprising eight items also proved valid and reliable. Testing of AddiQoL-30 in this large patient cohort showed significantly worse scores with increasing age and in women compared with men but no difference between patients with isolated AD and those with concomitant diseases. CONCLUSION: The validation process resulted in a revised 30-item AddiQoL questionnaire and an eight-item AddiQoL short version with good psychometric properties and high reliability.

Effect of antipsychotic-induced hyperprolactinemia on anthropometric measures, insulin sensitivity and lipid profile in patients with schizophrenia or related psychoses.

OBJECTIVES: This study consisting of two subprojects was undertaken to evaluate the effects of hyperprolactinemia on cardiovascular disease (CVD) risk parameters such as anthropometric measures, insulin sensitivity and blood lipids in patients with schizophrenia or related psychoses on long term treatment with antipsychotics. METHODS: In subproject Ι, 45 patients receiving the 2nd generation antipsychotics risperidone, clozapine or olanzapine were compared regarding prolactin (PRL), body mass index (BMI), insulin, homeostasis model assessment of insulin resistance (HOMA-IR) and blood lipids. In subproject Π, 24 patients receiving 1st or 2nd generation antipsychotics were investigated with diurnal profile of PRL and oral glucose tolerance test (OGTT). RESULTS: Elevated PRL levels were found in about 45% of the patients and occurred more often in patients receiving risperidone or haloperidol, compared to patients receiving clozapine or olanzapine. In contrast, in subproject Ι, insulin and HOMA-IR were higher and high density lipoprotein cholesterol was lower in patients receiving clozapine or olanzapine, compared with patients receiving risperidone. However, PRL levels did not correlate to BMI, insulin, HOMA-IR or lipids in any of these three treatment groups. In subproject Π, OGTT showed impaired glucose tolerance in 25% and new-onset diabetes in 4% of the 24 patients investigated. Additionally, the PRL (median 24 h) levels correlated positively to the 2 h glucose level at OGTT (rs=0.42, p=0.04). CONCLUSIONS: Our findings point to that hyperprolactinemia due to 1st and 2nd generation antipsychotics may decrease insulin sensitivity, whereas other mechanisms probably underlie insulin resistance induced by PRL-sparing antipsychotics such as clozapine and olanzapine.

Cancer risk in hyperprolactinemia patients: a population-based cohort study.

OBJECTIVE: Experimental evidence indicates that prolactin might play a role in tumorigenesis of several human cancers, but data on cancer risk in hyperprolactinemia patients are sparse. The aim of this study was to investigate cancer risk in hyperprolactinemia patients. Design A population-based matched cohort study in Sweden. METHODS: The hyperprolactinemia cohort consisted of patients hospitalized for hyperprolactinemia from 1987 to 1995 identified in the National Patient Register (n=585) and a hospital cohort of prolactinoma patients at Karolinska University Hospital (n=384). For each patient, ten matched individuals were identified via the Register of Population. Cancer occurrence was ascertained via the Swedish Cancer Registry. Hazard ratios (HRs) were estimated by Cox proportional hazards regression. RESULTS: Seventy-three malignant tumors were identified in the hyperprolactinemia patients and 660 tumors in the comparison group (HR 1.31; 95% confidence interval (CI): 1.02-1.68), mainly attributed to an increased risk of upper gastrointestinal cancer in both males and females (HR 3.69; 95% CI: 1.70-8.03) and hematopoietic cancer in females (HR 3.51; 95% CI: 1.06-11.6). Twelve breast cancers occurred in the female patients, corresponding to an HR of 1.09 (95% CI: 0.60-1.99). Prostate cancer risk in hyperprolactinemia men was reduced (HR 0.40; 95% CI: 0.16-0.99). CONCLUSIONS: An increased overall cancer risk was found in hyperprolactinemia patients, but no increased risk of breast cancer in women and a reduced risk of prostate cancer in men. These findings warrant further investigations and to be confirmed in larger studies but may indicate the importance of an active treatment strategy and follow-up of hyperprolactinemia patients.

Insulin sensitivity and lipid profile in prolactinoma patients before and after normalization of prolactin by dopamine agonist therapy.

Hyperprolactinemia has been associated with impaired metabolism, including insulin resistance. However, the metabolic effects of elevated prolactin (PRL) levels are not completely clarified. The aim of this study was to obtain more insights of metabolic consequences in hyperprolactinemia patients. Fourteen consecutive patients, eight women and six men, aged 39.7 (±13.7) years with prolactinomas (median PRL 72 [49-131] µg/L in women and 1,260 [123-9,600] µg/L in men) were included. Anthropometric data and metabolic values were studied before and after 2 and 6 months on DA agonists (Bromocriptine [5.7 (±3.9) mg/day, n = 13] or Cabergoline [0.5 mg/week, n = 1]). Euglycemic hyperinsulinemic clamps were studied in six patients before and after 6 months of treatment. PRL normalized in all patients. Anthropometric data changed only in males with a significant decrease of median body weight (95.6 [80.7-110.1] to 83.4 [77.8-99.1] kg, P = 0.046), waist circumference and fat percentage after 6 months. LDL cholesterol was positively correlated to PRL at diagnosis (r = 0.62, P = 0.025) and decreased within 2 months (3.4 [±0.9] to 2.9 [±0.6] mmol/L, P = 0.003). Insulin, IGFBP-1 and total adiponectin levels did not change. Insulin sensitivity tended to improve after 6 months; M-value from 5.7 (±1.8) to 7.8 (±2.6) mg/kg/min, P = 0.083 and per cent improvement in M-value was correlated to per cent reduction in PRL levels (r = -0.85, P = 0.034). In conclusion, beneficial metabolic changes were seen in prolactinoma patients after treatment with DA agonists, underscoring the importance of an active treatment approach and to consider the metabolic profile in the clinical management of hyperprolactinemia patients.

Serotonin receptor 2A gene polymorphisms and schizophrenia: association with family history, diagnostic subtype and height in patients.

OBJECTIVES: The 102T/C single nucleotide polymorphism (SNP) in the 5-hydroxytryptamine receptor 2A (HTR2A) gene has been reported to be associated with schizophrenia. However, SNPs of the HTR2A gene other than the 102T/C have attracted only limited studies in relation to schizophrenia, and also on the whole SNPs of the HTR2A gene have been little studied in relation to clinical parameters in patients. Therefore, the aim of this study was to evaluate the impact of main functionally characterized SNPs of the HTR2A gene on both the schizophrenia and clinical parameters. METHODS: Ninety-four patients with schizophrenia and 57 control subjects were genotyped for the -1438A/G, -783A/G, 102T/C and His452Tyr SNPs of the HTR2A gene. The four SNPs were then investigated in relation to the schizophrenia and clinical parameters. RESULTS: No differences were found in genotype-, allele- or haplotype frequencies between schizophrenia patients and control subjects. However, the 452Tyr variant of the His452Tyr polymorphism occurred more often in patients with a family history of schizophrenia compared with patients without heredity (p=0.028). The 452Tyr variant was also more common in female patients with paranoid schizophrenia than in those with non-paranoid schizophrenia (p=0.018). Moreover, the male patients carrying the A/A or T/T genotypes of the -1438A/G and 102T/C polymorphisms were shorter than those carrying the G/A or C/T genotypes (p=0.007; p=0.006). CONCLUSION: The present findings bring further support to the view that the -1438A/G, 102T/C and His452Tyr polymorphisms of the HTR2A gene are connected with a constitutive cellular change that causes susceptibility to schizophrenia.