Increased Resting-State Functional Connectivity in Patients With Autoimmune Addison Disease.

CONTEXT: Individuals with autoimmune Addison disease (AAD) take replacement medication for the lack of adrenal-derived glucocorticoid (GC) and mineralocorticoid hormones from diagnosis. The brain is highly sensitive to these hormones, but the consequence of having AAD for brain health has not been widely addressed. OBJECTIVE: The present study compared resting-state functional connectivity (rs-fc) of the brain between individuals with AAD and healthy controls. METHODS: Fifty-seven patients with AAD (33 female) and 69 healthy controls (39 female), aged 19 to 43 years were scanned with 3-T magnetic resonance imaging (MRI). RESULTS: Independent component and subsequent dual regression analyses revealed that individuals with AAD had stronger rs-fc compared to controls in 3 networks: the bilateral orbitofrontal cortex (OFC), the left medial visual and left posterior default mode network. A higher GC replacement dose was associated with stronger rs-fc in a small part of the left OFC in patients. We did not find any clear associations between rs-fc and executive functions or mental fatigue. CONCLUSION: Our results suggest that having AAD affects the baseline functional organization of the brain and that current treatment strategies of AAD may be one risk factor.

Growth and Treatment in Congenital Adrenal Hyperplasia: An Observational Study from Diagnosis to Final Height.

Introduction Congenital adrenal hyperplasia (CAH) due to 21α-hydroxylase deficiency results in inadequate cortisol and aldosterone synthesis and concomitant overproduction of adrenal androgens. Despite adequate replacement, impaired growth and overweight remains a clinical challenge. The main objective was to investigate the differences in growth, final height (FH), and body mass index (BMI) between different CYP21A2 genotype groups and glucocorticoid treatment strategies during the different phases of growth. Methods This is a population based observational cohort study from diagnosis to final height (FH). A total of 86 subjects were diagnosed with CAH in Sweden during 1989-1994. Eighty subjects were followed until FH. There were no intervention apart from the clinical standard of care treatment for CAH. The main outcome measure was the corrected FH standard deviation score (cFH SDS) and its correlation with genotype, accumulated total glucocorticoid dose, and treatment strategy. In addition, BMI and growth trajectories during infancy, childhood, and adolescence were studied. Results FH was shorter in patients with the more severe CYP21A2 genotypes. Treatment doses of glucocorticoid were within the international treatment recommendations (10-15 mg/m2). Patients with the null and I2 splice genotypes lost approximately 1 SD in final height whereas patients with the milder genotypes (I172N, P30L and V281L) were within 0.5 to 0 SDS from target height. cFH SDS was negatively affected by the use of prednisolone but did not correlate with overall glucocorticoid treatment dose calculated as hydrocortisone equivalents. BMI at 18 years was higher in patients treated with prednisolone but did not correlate with genotype. Conclusions Corrected final height was more affected in patients with severe CYP21A2 genotypes. The addition of a low dose of prednisolone to the hydrocortisone treatment, despite an equivalent total dose of glucocorticoids, was associated with shorter FH and higher BMI in growing subjects with CAH.

An update on the long-term outcomes of prenatal dexamethasone treatment in congenital adrenal hyperplasia.

First-trimester prenatal treatment with glucocorticoid (GC) dexamethasone (DEX) in pregnancies at risk for classic congenital adrenal hyperplasia (CAH) is associated with ethical dilemmas. Though effective in reducing virilisation in girls with CAH, it entails exposure to high doses of GC in fetuses that do not benefit from the treatment. The current paper provides an update on the literature on outcomes of prenatal DEX treatment in CAH cases and unaffected subjects. Long-term follow-up research is still needed to determine treatment safety. In addition, advances in early prenatal diagnostics for CAH and sex-typing as well as studies assessing dosing effects of DEX may avoid unnecessary treatment and improve treatment safety.

Brain activity during visuospatial working memory in congenital adrenal hyperplasia.

CONTEXT: Patients with congenital adrenal hyperplasia (CAH) require life-long replacement of cortisol. Problems with cognitive function, especially working memory, have previously been identified, but the long-term effects of this disease on brain function are unknown. OBJECTIVE: We investigate brain activity during working memory in CAH compared to controls. DESIGN, SETTING, AND PARTICIPANTS: Twenty-nine individuals with CAH (17 females) and 40 healthy controls (24 females), 16-33 years, from a single research institute, underwent functional magnetic resonance imaging while doing a verbal and visuospatial working memory task. RESULTS: Individuals with CAH responded faster on the verbal task. Although we found no differences in BOLD response over the whole group, there were significant interactions with sex: CAH males had increased activity in the bilateral lateral superior occipital cortex, left supramarginal and angular gyri, left precuneus, left posterior cingulate cortex and bilateral cerebellum during decoding of the visuospatial task, while females showed decreased activity in these regions. CONCLUSIONS: Long-term cortisol imbalances do not seem to have a major impact on the functional brain responses during working memory in CAH. However, activity of the left dorsal visual stream in particular might be affected depending on sex. As the task employed may have been relatively easy, larger studies using more complex tasks are needed to further investigate this.

Transition Readiness in Adolescents and Young Adults Living With Congenital Adrenal Hyperplasia.

OBJECTIVE: Congenital adrenal hyperplasia (CAH) refers to a group of genetic disorders that affect cortisol biosynthesis and the need for glucocorticoid treatment is lifelong. The complexities of CAH can greatly affect teenage life and the transition from pediatric to adult care. The aim was to assess transition readiness and the impact on quality of life (QoL) as well as medication adherence rates in adolescents and young adults with CAH. METHODS: Prospective assessment of transition readiness was conducted through standardized questionnaires for adolescents and young adults (aged 16-35 years). Four open-ended questions on self-care were summarized in adolescents (aged 18-19 years) and their parents. Transition readiness was assessed using a modified CAH specific questionnaire: "Transition preparation and readiness to transfer from pediatric to adult care" with a cutoff level of >25 defined as good transition readiness. Measurement of QoL was performed using Rand 36. Medication adherence rate was measured using the self-reported questionnaire Adherence Starts with Knowledge. RESULTS: Thirty-eight adolescents and young adults with CAH were included in the study. Transition readiness was classified as good in 26 (68%) of the participants. Good transition readiness was more frequent in participants with good medication adherence rates. A general linear model analysis showed a good transition readiness affected QoL by increasing QoL scores. CONCLUSION: Self-reported transition readiness was found in the majority of adolescents and young adults with CAH. A good medication adherence rate was associated with a better transition readiness and a good transition readiness was associated with increased QoL scores.

Brain structure in autoimmune Addison's disease.

Long-term disturbances in cortisol levels might affect brain structure in individuals with autoimmune Addison's disease (AAD). This study investigated gray and white matter brain structure in a cohort of young adults with AAD. T1- and diffusion-weighted images were acquired for 52 individuals with AAD and 70 healthy controls, aged 19-43 years, using magnetic resonance imaging. Groups were compared on cortical thickness, surface area, cortical gray matter volume, subcortical volume (FreeSurfer), and white matter microstructure (FSL tract-based spatial statistics). Individuals with AAD had 4.3% smaller total brain volume. Correcting for head size, we did not find any regional structural differences, apart from reduced volume of the right superior parietal cortex in males with AAD. Within the patient group, a higher glucocorticoid (GC) replacement dose was associated with smaller total brain volume and smaller volume of the left lingual gyrus, left rostral anterior cingulate cortex, and right supramarginal gyrus. With the exception of smaller total brain volume and potential sensitivity of the parietal cortex to GC disturbances in men, brain structure seems relatively unaffected in young adults with AAD. However, the association between GC replacement dose and reduced brain volume may be reason for concern and requires follow-up study.

Congenital adrenal hyperplasia.

Congenital adrenal hyperplasia is a group of autosomal recessive disorders leading to multiple complex hormonal imbalances caused by various enzyme deficiencies in the adrenal steroidogenic pathway. The most common type of congenital adrenal hyperplasia is due to steroid 21-hydroxylase (21-OHase, henceforth 21OH) deficiency. The rare, classic (severe) form caused by 21OH deficiency is characterised by life-threatening adrenal crises and is the most common cause of atypical genitalia in neonates with 46,XX karyotype. After the introduction of life-saving hormone replacement therapy in the 1950s and neonatal screening programmes in many countries, nowadays neonatal survival rates in patients with congenital adrenal hyperplasia are high. However, disease-related mortality is increased and therapeutic management remains challenging, with multiple long-term complications related to treatment and disease affecting growth and development, metabolic and cardiovascular health, and fertility. Non-classic (mild) forms of congenital adrenal hyperplasia caused by 21OH deficiency are more common than the classic ones; they are detected clinically and primarily identified in female patients with hirsutism or impaired fertility. Novel treatment approaches are emerging with the aim of mimicking physiological circadian cortisol rhythm or to reduce adrenal hyperandrogenism independent of the suppressive effect of glucocorticoids.

Current and Novel Treatment Strategies in Children with Congenital Adrenal Hyperplasia.

BACKGROUND: The standard treatment for congenital adrenal hyperplasia (CAH) in children is still hydrocortisone. Improved strategies for timing of the dose during the day and the dose per square meter body surface area used in children of different ages and developmental phases have improved the situation and outcome for the patients. Neonatal screening enables an earlier diagnosis and initiation of treatment, prevents from adrenal crisis, and improves growth and development also for children with the less severe forms of CAH. SUMMARY: This review describes the current treatment strategies for children with CAH and discusses some potential treatment options that have been developed with the primary aim to decrease the adrenal androgen production. Novel modified release glucocorticoid therapies are also discussed. KEY MESSAGES: The long-term effects of the new adjunct therapies are unknown, and some are not suitable for use in children and adolescents. The effects of the new therapies on bone mineral density, gonadal functions, and long-term cognitive development are yet to be assessed. It is not known what levels of adrenal androgens are optimal for normal growth, puberty, and bone health. The basis of using glucocorticoids and mineralocorticoids in the treatment of CAH remains, and in some individuals, it may be beneficial to add therapies to reduce the androgen load during certain life stages.

First Trimester Dexamethasone Treatment Is Not Associated With Alteration in Resting-state Connectivity at Adolescent or Adult Age.

CONTEXT: Prenatal treatment with dexamethasone (DEX) has been used to prevent virilization in females at risk of congenital adrenal hyperplasia (CAH). Both affected and unaffected girls, as well boys, are treated until the genotype and sex of the fetus is known (gestational weeks 10-12). After that, only affected girls are treated until term. Exposure to a high synthetic glucocorticoid dosage may alter the developmental trajectory of the brain, with alterations in resting-state functional connectivity of the brain at adult age. OBJECTIVE: To investigate resting-state functional connectivity in subjects at risk of having CAH, exposed to DEX treatment during the first trimester of fetal life, both in the whole brain and in 3 regions of interest (amygdala, hippocampus, and superior frontal gyrus). DESIGN, SETTING, AND PARTICIPANTS: Eighteen participants (8 females) at risk of having CAH, exposed to DEX treatment, and 38 controls (24 females), age range 16 to 26 years, from a single research institute, underwent functional magnetic resonance imaging of the brain during rest. We used 2 different approaches: an exploratory whole-brain analysis and seed-based analysis. For seed-based analysis, we chose 3 different brain regions (amygdala, hippocampus, and superior frontal gyrus) based on our previous findings and literature evidence. RESULTS: We did not observe any differences in functional connectivity during rest, either in the whole brain nor in seed-based connectivity analyses at this adolescent and young adult age. CONCLUSIONS: Our results are reassuring; however, future studies on larger samples and with more sensitive methodologies are needed to confirm these findings.

Long-Term Outcomes of Congenital Adrenal Hyperplasia.

A plethora of negative long-term outcomes have been associated with congenital adrenal hyperplasia (CAH). The causes are multiple and involve supra-physiological gluco- and mineralocorticoid replacement, excess adrenal androgens both intrauterine and postnatal, elevated steroid precursor and adrenocorticotropic hormone levels, living with a congenital condition as well as the proximity of the cytochrome P450 family 21 subfamily A member 2 (CYP21A2) gene to other genes. This review aims to discuss the different long-term outcomes of CAH.

Changes in resting-state functional connectivity in patients with congenital adrenal hyperplasia.

CONTEXT: Patients with congenital adrenal hyperplasia (CAH) are treated with life-long glucocorticoid (GC) replacement therapy. Negative effects on cognition, brain structure and function during working memory tasks have been identified. To date, no studies on functional connectivity during rest have been performed in patients with CAH. OBJECTIVE: To investigate resting-state functional connectivity in patients with CAH compared with healthy untreated controls and the association between functional connectivity in the precuneus and disease severity, dose of GC and working memory (WM). DESIGN, SETTING AND PARTICIPANTS: Thirty-one patients with CAH (18 females) and 38 healthy controls (24 females), aged 16-33 years, from a single research institute, underwent functional magnetic resonance imaging of the brain during rest. RESULTS: Patients with CAH showed increased functional connectivity in the precuneus compared with controls. Post-hoc tests within the precuneus showed that only patients with simple virilising CAH had stronger connectivity compared to controls. Further, while both patients with salt-wasting and simple virilising CAH performed worse on a WM task compared to controls, functional connectivity in the precuneus was not associated with executive function performance. CONCLUSION: Patients with CAH demonstrated altered functional connectivity during rest in the precuneus. Such a change may reflect a functional reorganisation in response to the CAH disease. The change in functional connectivity may depend on the severity of CAH.

Young adult Swedish patients with autoimmune Addison's disease report difficulties with executive functions in daily life despite overall good cognitive performance.

OBJECTIVES: Sub-optimal replacement of glucocorticoids (GC) in autoimmune Addison's disease (AAD) may affect cognitive functioning. The present study therefore sought to investigate cognitive performance and self-reported problems with executive functions in a cohort of young adult patients with AAD. DESIGN AND METHODS: 67 patients with AAD (39 females), mean age 32 yrs. (range 19-41), and 80 control participants (43 females), mean age 29 yrs. (range 19-43), completed neuropsychological tests estimating verbal and non-verbal intellectual ability, learning, memory and executive functioning, in addition to self-report scales assessing problems with executive functions, fatigue and symptoms of anxiety and depression. RESULTS: Patients performed within the average range on all cognitive tests compared to population norms. However, female AAD patients reported more problems than controls with both hot (emotion regulation) and cold (cognitive regulation) executive functions in daily life. Moreover, experienced problems with executive functions in both male and female patients were associated with increased mental fatigue and lower GC replacement doses. CONCLUSIONS: Despite average performance in neuropsychological tests by both sexes, young adult female patients with AAD experience problems with executive functions in daily life. Coping with mental fatigue and optimization of pharmacotherapy may be important factors to be addressed in order to provide timely support for patients. Future research is needed to further determine other risk factors for experiencing executive function impairments in AAD.

Very long-chain acyl-CoA dehydrogenase deficiency in a Swedish cohort: Clinical symptoms, newborn screening, enzyme activity, and genetics.

Very long-chain acyl-CoA dehydrogenase deficiency (VLCADD) is a recessive disorder of fatty acid beta-oxidation with variable phenotype. Patients may present during the neonatal period with lethal multi-organ failure or during adulthood with a myopathic phenotype. VLCADD is included in the Swedish newborn screening (NBS) program since 2010. The study describes the phenotype and biochemical findings in relation to the genotype, enzyme activity, and screening data in a Swedish cohort of pediatric patients with VLCADD. A total of 22 patients (20 diagnosed via NBS between 2010 and 2019, two diagnosed pre NBS) were included. Parameters analyzed were enzyme activity (palmitoyl CoA oxidation rate); ACADVL genotype; NBS results including Collaborative Laboratory Integrated Reports (CLIR) score; biochemical findings; treatment; clinical outcome. A clinical severity score (CSS) was compiled using treatment interventions and clinical symptoms. A possible correlation between CSS and VLCAD residual enzyme activity and NBS CLIR score was analyzed. The most common ACADVL variant (c.848T>C) was identified in 24/44 alleles. Five novel variants were detected. Clinical manifestations varied from asymptomatic to severe. There was a correlation between CSS, residual enzyme activity, and CLIR scores. Most patients diagnosed via NBS had less severe disease compared to those clinically diagnosed. In conclusion, the identified correlation between the NBS CLIR score, residual enzyme activity, and clinical outcome suggests that information available neonatally may aid in treatment decisions.

Prenatal dexamethasone treatment for classic 21-hydroxylase deficiency in Europe.

Objective: To assess the current medical practice in Europe regarding prenatal dexamethasone (Pdex) treatment of congenital adrenal hyperplasia (CAH) due to 21-hydroxylase deficiency. Design and methods: A questionnaire was designed and distributed, including 17 questions collecting quantitative and qualitative data. Thirty-six medical centres from 14 European countries responded and 30 out of 36 centres were reference centres of the European Reference Network on Rare Endocrine Conditions, EndoERN. Results: Pdex treatment is currently provided by 36% of the surveyed centres. The treatment is initiated by different specialties, that is paediatricians, endocrinologists, gynaecologists or geneticists. Regarding the starting point of Pdex, 23% stated to initiate therapy at 4-5 weeks postconception (wpc), 31% at 6 wpc and 46 % as early as pregnancy is confirmed and before 7 wpc at the latest. A dose of 20 µg/kg/day is used. Dose distribution among the centres varies from once to thrice daily. Prenatal diagnostics for treated cases are conducted in 72% of the responding centres. Cases treated per country and year vary between 0.5 and 8.25. Registries for long-term follow-up are only available at 46% of the centres that are using Pdex treatment. National registries are only available in Sweden and France. Conclusions: This study reveals a high international variability and discrepancy in the use of Pdex treatment across Europe. It highlights the importance of a European cooperation initiative for a joint international prospective trial to establish evidence-based guidelines on prenatal diagnostics, treatment and follow-up of pregnancies at risk for CAH.

Ambulatory Blood Pressure Monitoring in Children and Adults Prenatally Exposed to Dexamethasone Treatment.

CONTEXT: The clinical use of dexamethasone (DEX) prenatally to reduce virilization of external genitalia in female fetuses with congenital adrenal hyperplasia (CAH) is efficient but still controversial. It remains challenging to prevent the excessive exposure of DEX in unborn healthy babies during the first trimester of pregnancy. OBJECTIVE: Since endogenous glucocorticoids contribute to the maintenance of blood pressure (BP) and since events during fetal life may program the fetus and affect future metabolic health, the aim of this study was to analyze ambulatory BP measurements in CAH-unaffected children and adults that were prenatally exposed to DEX treatment. METHODS: Ambulatory BP measurements were analyzed in 33 (16 female) DEX-treated participants aged 5.1 to 26.3 years (19 participants aged ≤ 18 years) and in 54 (28 female) age- and sex-matched apparently healthy controls aged 5.5 to 25.3 years (27 participants aged ≤ 18 years) with ambulatory normotension. RESULTS: Participants' age, height, weight, and body mass index were similar between the DEX-treated group and the control group. Heart rate, 24-hour BP, pulse pressure, and nighttime dipping did not statistically significantly differ between DEX-treated participants and controls. CONCLUSION: Our study suggests that prenatal DEX treatment in CAH-unaffected children and adults does not appear to adversely affect ambulatory BP later in life. Our observations need to be confirmed in larger studies.

The impact of adherence and therapy regimens on quality of life in patients with congenital adrenal hyperplasia.

OBJECTIVE: Varying outcomes regarding the quality of life (QoL) have been reported in patients with congenital adrenal hyperplasia (CAH). To assess the impact of adherence rate to medical therapy regimens on QoL in patients with CAH. PATIENTS: Adolescents and adults aged 15-72 years with CAH due to 21-hydroxylase deficiency at Karolinska University Hospital, Stockholm, Sweden. MEASUREMENTS: QoL was assessed using the Addison QoL (n = 72) and RAND 36 questionnaires (n = 75). Adherence to therapy regimens was measured using the Adherence Starts with Knowledge questionnaire (ASK-12). Associations between QoL, type of glucocorticoid therapy prescribed and ASK-12 results were examined. Results were compared to reference RAND 36 data obtained from a representative sample from the general Swedish population. RESULTS: A good adherence rate to therapy regimens and a younger age were key factors for a better QoL in study participants with CAH. Younger patients on hydrocortisone and with good adherence had higher RAND 36 scores than older patients on prednisolone independently adherence. Participants with classic CAH (both the salt-wasting and simple virilizing form) reported higher QoL than those with nonclassic CAH. Patients with CAH, especially nonclassic, more frequently reported an impaired QoL than the general population, especially regarding limitations related to body pain, vitality and mental health. CONCLUSION: A poor adherence rate to therapy regimens, rather than type of glucocorticoid was associated with impaired QoL in adolescents and adults with CAH.

Clinical outcomes in 21-hydroxylase deficiency.

PURPOSE OF REVIEW: The introduction of synthetic glucocorticoids 70 years ago made survival possible in classic 21-hydroxylase deficiency (21OHD). The currently used glucocorticoid therapy may lead to unphysiological dosing with negative consequencies on health in addition to the problems that may arise due to androgen over-exposure. RECENT FINDINGS: Fertility in females with 21OHD seemed to be impaired, especially in the salt-wasting (SW) phenotype but when pregnancies did occur there was a higher risk for gestational diabetes and cesearean section. Increased fat mass, body mass index, insulin resistance and frequency of autoimmune disorders as well as impaired echocardiographic parameters and lower bone mineral density were found in 21OHD compared to controls. Negative effects on cognitive functions have been identified. Adrenal tumors, especially myelolipomas, were prevalent. Increased knowledge on steroid metabolism in 21OHD and urine steroid profiling may improve assessment of treatment efficacy. Nevanimibe, abiraterone acetate and anastrozole may have a place in the future management of 21OHD. Long-acting glucocorticoids may be a less favorable, especially dexamethasone. SUMMARY: The various clinical outcomes need regular monitoring. Negative consequencies are to large extent the result of the unphysiological glucocorticoid replacement. Modern management with improved follow-up and future addition of new drugs may improve outcomes.

Therapy options for adrenal insufficiency and recommendations for the management of adrenal crisis.

Adrenal insufficiency (AI) is a life-threatening condition requiring life-long glucocorticoid (GC) substitution therapy, as well as stress adaptation to prevent adrenal crises. The number of individuals with primary and secondary adrenal insufficiency in Europe is estimated to be 20-50/100.000. A growing number of AI cases are due to side effects of GC treatment used in different treatment strategies for cancer and to immunotherapy in cancer treatment. The benefit of hormone replacement therapy is evident but long-term adverse effects may arise due to the non-physiological GC doses and treatment regimens used. Given multiple GC replacement formulations available comprising short-acting, intermediate, long-acting and novel modified-release hydrocortisone as well as subcutaneous formulations, this review offers a concise summary on the latest therapeutic improvements for treatment of AI and prevention of adrenal crises. As availability of various glucocorticoid formulations and access to expert centers across Europe varies widely, European Reference Networks on rare endocrine conditions aim at harmonizing treatment and ensure access to specialized patient care for individual case-by-case treatment decisions. To improve the availability across Europe to cost effective oral and parenteral formulations of hydrocortisone will save lives.

Assessment of medication adherence in children and adults with congenital adrenal hyperplasia and the impact of knowledge and self-management.

BACKGROUND: Congenital adrenal hyperplasia (CAH) is caused by a deficiency of one of the enzymes required for cortisol biosynthesis. The disease is classified as either classic (severe phenotype), subdivided into simple virilizing (SV) and salt-wasting (SW), or non-classic (NC) CAH. The treatment regime involves life-long glucocorticoid replacement, especially in classic phenotype. OBJECTIVES: We aimed to assess medication adherence, endocrine knowledge and self-management in patients with CAH and to compare patients' and physicians' assessments of medication adherence. METHODS: A prospective cross-sectional study of 108 patients with CAH (52 children and 56 adults) and 45 parents/caregivers. Two adherence measures were used, a self-reported questionnaire named Adherence Starts with Knowledge (ASK-12) with a cut-off level > 22 defined as poor adherence rate, and an assessment by a physician based on growth rate, 17-hydroxyprogesterone profile, and medical history, ranked using a five-point Likert scale. Measurements of the patients'/parents' knowledge and self-management were performed using Endocrine Society Clinical Practice Guidelines. RESULTS: Self-reported medication adherence was good with 74% of the participants reported good adherence with higher adherence in patients with the SW form. The highest endocrine knowledge and self-management were found in parents compared with children and adults with classic CAH. There was 30% discordance between the assessments by a physician and the self-reported ASK-12 scores independent of the severity of CAH. CONCLUSION: Patients and endocrinologists reported high medication adherence, however, discordance was found in 30% of the studied patients. Patients with the more severe form of CAH had higher adherence rates and demonstrated good endocrine knowledge/self-management.

Update on the Swedish Newborn Screening for Congenital Adrenal Hyperplasia Due to 21-Hydroxylase Deficiency.

Congenital adrenal hyperplasia (CAH) was the fourth disorder added to the national Swedish neonatal screening program in 1986, and approximately 115,000 newborns are screened annually. Dried blood spot (DBS) screening with measurement of 17-hydroxyprogesterone (17OHP) is also offered to older children moving to Sweden from countries lacking a national DBS screening program. Here, we report an update on the CAH screening from January 2011 until December 2019. Results: During the study period, 1,030,409 newborns and 34,713 older children were screened. In total, 87 newborns were verified to have CAH, which gives an overall positive predictive value (PPV) of 11% and 21% for term infants. Including the five missed CAH cases identified during this period, this gives an incidence of 1:11,200 of CAH in Sweden. Among the older children, 12 of 14 recalled cases were found to be true positive for CAH. All patients were genotyped as part of the clinical follow-up and 70% of the newborns had salt wasting (SW) CAH and 92% had classic CAH (i.e., SW and simple virilizing (SV) CAH). In the group of 12 older children, none had SW CAH and two had SV CAH. Conclusion: The incidence of classic CAH is relatively high in Sweden. Early genetic confirmation with CYP21A2 genotyping has been a valuable complement to the analysis of 17OHP to predict disease severity, make treatment decisions and for the follow-up and evaluation of the screening program.