Surviving COVID-19 in Bergamo province: a post-acute outpatient re-evaluation.

Bergamo province was badly hit by the coronavirus disease 2019 (COVID-19) epidemic. We organised a public-funded, multidisciplinary follow-up programme for COVID-19 patients discharged from the emergency department or from the inpatient wards of 'Papa Giovanni XXIII' Hospital, the largest public hospital in the area. As of 31 July, the first 767 patients had completed the first post-discharge multidisciplinary assessment. Patients entered our programme at a median time of 81 days after discharge. Among them, 51.4% still complained of symptoms, most commonly fatigue and exertional dyspnoea, and 30.5% were still experiencing post-traumatic psychological consequences. Impaired lung diffusion was found in 19%. Seventeen per cent had D-dimer values two times above the threshold for diagnosis of pulmonary embolism (two unexpected and clinically silent pulmonary thrombosis were discovered by investigating striking D-dimer elevation). Survivors of COVID-19 exhibit a complex array of symptoms, whose common underlying pathology, if any, has still to be elucidated: a multidisciplinary approach is fundamental, to address the different problems and to look for effective solutions.

Does denosumab exert a protective effect against COVID-19? Results of a large cohort study.

Introduction: Denosumab is a monoclonal antibody blocking the receptor activator of nuclear factor kappa-B/receptor activator of nuclear factor kappa-B ligand (RANK/RANKL) pathway, thus inhibiting osteoclastogenesis. Since RANK and RANKL are also involved in the immune system activation, denosumab might interfere with the response against infections. Our study aimed to explore the relationship between denosumab treatment and coronavirus disease 2019 (COVID-19). Design and methods: The occurrence and severity of COVID-19 were recorded in consecutive patients referred to the Endocrinology Department of Papa Giovanni XXIII Hospital, Bergamo, from 1 January 2020 to 1 January 2021. Patients treated with denosumab were compared to outpatient controls. Patients' features were summarized by descriptive statistics. Multivariate logistic regression assessed the relationship between denosumab and COVID-19, adjusting for potential confounders. Subgroup analyses according to age, sex, body mass index (BMI), smoking status, and vitamin D levels were performed. Results: The final population included 331 patients treated with denosumab and 357 controls. COVID-19 incidence was lower in the denosumab group (7.6% vs. 14.6%, p = 0.004). COVID-19 severity was similar in both groups. Multiple logistic regression confirmed an association between denosumab and a reduced occurrence of symptomatic COVID-19 [odds ratio (OR) 0.46, 95% CI 0.21-0.98, p = 0.049]. Subgroup analyses suggested a potential protective effect of denosumab in patients over 75 years (OR 0.12, 95% CI 0.02-0.6, p = 0.011), with a significant interaction between denosumab and age categories (p = 0.047). Conclusion: Our study confirms that denosumab may be safely continued in COVID-19 patients. RANK/RANKL inhibition seems associated with a reduced incidence of symptomatic COVID-19, particularly among the elderly.

Increased prevalence of autoimmune thyroid disease after COVID-19: A single-center, prospective study.

Introduction: Thyroid dysfunctions associated with SARS-CoV-2 acute infection have been extensively described since the beginning of COVID-19 pandemics. Conversely, few data are available on the occurrence of thyroid autoimmunity after COVID-19 resolution. We assessed the prevalence of autoimmune thyroid disease (ATD) and thyroid dysfunctions in COVID-19 survivors three months after hospital admission. Design and methods: Single-center, prospective, observational, cohort study performed at ASST Papa Giovanni XXIII Hospital, Bergamo, Italy. 599 COVID-19 survivors were prospectively evaluated for thyroid function and autoimmunity thyroperoxidase antibodies (TPOAb), thyroglobulin antibodies (TgAb). When a positive antibody concentration was detected, thyroid ultrasound was performed. Multiple logistic regression model was used to estimate the association between autoimmunity and demographic characteristics, respiratory support, and comorbidities. Autoimmunity results were compared to a cohort of 498 controls referred to our Institution for non-thyroid diseases before the pandemic onset. A sensitivity analysis comparing 330 COVID-19 patients with 330 age and sex-matched controls was performed. Results: Univariate and multivariate analysis found that female sex was positively associated (OR 2.01, SE 0.48, p = 0.003), and type 2 diabetes (T2DM) was negatively associated (OR 0.36, SE 0.16, p = 0.025) with thyroid autoimmunity; hospitalization, ICU admission, respiratory support, or COVID-19 treatment were not associated with thyroid autoimmunity (p > 0.05). TPOAb prevalence was greater in COVID-19 survivors than in controls: 15.7% vs 7.7%, p = 0.002. Ultrasonographic features of thyroiditis were present in 94.9% of the evaluated patients with positive antibodies. TSH was within the normal range in 95% of patients. Conclusions: Autoimmune thyroid disease prevalence in COVID-19 survivors was doubled as compared to age and sex-matched controls, suggesting a role of SARS-CoV-2 in eliciting thyroid autoimmunity.

Switching to the Minimed™ 780G system achieves clinical targets for CGM in adults with type 1 diabetes regardless of previous insulin strategy and baseline glucose control.

AIMS: Advanced hybrid closed-loop (AHCL) systems represent the latest introduction in the treatment of type 1 diabetes (T1DM). Randomized controlled trials and real-world evidence studies showed that AHCL systems are a safe and effective insulin management strategy. Aim of this retrospective, single-center, real-life study was to evaluate the effect on metabolic control, evaluated by continuous glucose monitoring (CGM) metrics, of the switch from four available insulin strategies to an AHCL system in adult patients with type 1 diabetes. METHODS: A total of 102 patients with T1DM (mean age 42.1 ± 16.3 years, males/females 47/55, duration of diabetes 21.4 ± 13.3 years, BMI 24.4 ± 4.5 kg/m2, HbA1c 59.9 ± 9.6 mmol/mol or 7.6 ± 0.9%), treated with four different insulin therapies [multiple daily insulin (MDI) therapy, continuous subcutaneous insulin infusion (CSII), sensor-augmented pump (SAP) with predictive low-glucose suspend (PLGS), and hybrid closed loop (HCL) system] were evaluated before hand, two months and six months after switching to an AHCL (Minimed™ 780G system, Medtronic, Northridge, CA) system. RESULTS: Two months after the switch, mean GCM metrics improved in all four treatment groups. Six months after the switch, the participants of all four groups achieved a mean GMI < 53 mmol/mol, TIR > 70%, TBR < 4%, and CV < 36%, which is recommended by the ADA Standard of Medical Care in Diabetes 2022, including the MDI group with worse baseline glycemic control. CONCLUSIONS: Switching to an AHCL leads to a rapid improvement in glycemic control lasting for up to six months independently of previous insulin treatment and baseline conditions.

Predictors of bone responsiveness to growth hormone (GH) replacement in adult GH-deficient patients.

Growth hormone (GH) replacement in adulthood results in variable bone responses as a function of the gonadic hormonal milieu. We performed a retrospective analysis of a large cohort of adult males and females with confirmed GH deficiency (GHD) prior to treatment and during 3 years of replacement therapy. Potential confounders and effect modifiers were taken into account. Sixty-four adult patients with GHD (20 females and 44 males; mean age 34 years, range 18-64) were included in the analysis. GH replacement induced a different effect on bone in males compared to females. Bone mineral content increased in males and decreased in females at the lumbar spine, total femur, and femoral neck; bone mineral density showed a similar trend at the lumbar spine and femoral neck. There was no significant gender difference in bone area at any measured bone site. In both sexes we observed a similar trend for serum markers of bone remodeling. Sex predicted bone outcome on multivariate analysis, as did age, onset of GHD (childhood/adulthood), pretreatment bone mass, baseline body mass index (BMI), and BMI change during GH replacement. Serum IGF-I levels during treatment did not show any relationship with bone outcome at any measured site. This study confirms that bone responsiveness to GH replacement in adult GHD varies as a function of sex even after controlling for potential confounders and highlights the importance of other cofactors that may affect the interaction between GH replacement therapy and bone remodeling.

Effects of SGLT2 Inhibitors and GLP-1 Receptor Agonists on Renin-Angiotensin-Aldosterone System.

Sodium-glucose cotransporters inhibitors (SGLT2-i) and GLP-1 receptor agonists (GLP1-RA) are glucose-lowering drugs that are proved to reduce the cardiovascular (CV) risk in type 2 diabetes mellitus (T2DM). In this process, the renin-angiotensin-aldosterone system (RAAS) is assumed to play a role. The inhibition of SGLT2 improves hyperglycemia hampering urinary reabsorption of glucose and inducing glycosuria. This "hybrid" diuretic effect, which couples natriuresis with osmotic diuresis, potentially leads to systemic RAAS activation. However, the association between SGLT2-i and systemic RAAS activation is not straightforward. Available data indicate that SGLT2-i cause plasma renin activity (PRA) increase in the early phase of treatment, while PRA and aldosterone levels remain unchanged in chronic treated patients. Furthermore, emerging studies provide evidence that SGLT2-i might have an interfering effect on aldosterone/renin ratio (ARR) in patients with T2DM, due to their diuretic and sympathoinhibition effects. The cardio- and reno-protective effects of GLP-1-RA are at least in part related to the interaction with RAAS. In particular, GLP1-RA counteract the action of angiotensin II (ANG II) inhibiting its synthesis, increasing the inactivation of its circulating form and contrasting its action on target tissue like glomerular endothelial cells and cardiomyocytes. Furthermore, GLP1-RA stimulate natriuresis inhibiting Na+/H+ exchanger NHE-3, which is conversely activated by ANG II. Moreover, GLP1 infusion acutely reduces circulating aldosterone, but this effect does not seem to be chronically maintained in patients treated with GLP1-RA. In conclusion, both SGLT2-i and GLP1-RA seem to have several effects on RAAS, though additional studies are needed to clarify this relationship.

Bone and body composition analyses by DXA in adults with GH deficiency: effects of long-term replacement therapy.

PURPOSE: The effects of growth hormone (GH) replacement on bone mass and body composition in adult with GH deficiency (AGHD) are still debated with regard to their persistence in the long term. Moreover, the impact of the gender on the response to GH is controversial. Aim of this study was to evaluate the long-term effects of rhGH replacement on bone mass and body composition in a monocentric cohort of patients with AGHD. METHODS: Data from 118 patients with AGHD (34.8 ± 14.4 years, 43 women and 75 men) treated with rhGH for a period of at least 3 years up to a maximum of 10 were retrospectively collected. Bone mineral density (BMD) at the lumbar spine, femur, and 1/3 radius, and total and truncular body composition were evaluated by dual-energy X-ray absorption (DXA) before and during treatment. Clinical and laboratory evaluations were performed before and during the treatment period on an annual basis. RESULTS: Lumbar spine BMD consistently increased in males, while it decreased in females after a transient improvement observed during the first 4 years of therapy. There were no significant changes in femoral and 1/3 radial BMD in either sexes. Lean mass significantly increased in both sexes, while fat mass only decreased in males. CONCLUSIONS: In AGHD patients long-term rhGH replacement therapy induces a positive effect with regard to bone mass and body composition. A sexual dimorphism in the response to treatment is evident, with males displaying a more favorable outcome.

Effect of Denosumab on Glucose Homeostasis in Postmenopausal Women with Breast Cancer Treated with Aromatase Inhibitors: A Pilot Study.

BACKGROUND: Aromatase inhibitors in women with breast cancer have been associated with cancer treatment-induced bone loss (CTIBL), increased fracture risk, and impairment of glucose metabolism. Denosumab (Dmab), a monoclonal antibody against RANKL, which is a key regulator of the osteoclast activity, is effective as an antiresorptive agent in the treatment of CTIBL. Since RANKL/RANK pathway may contribute to the pathogenesis of glucometabolic disorders, it has been suggested that Dmab may improve glucose homeostasis. Our pilot study evaluated the effect of a single administration of 60 mg Dmab on glucose metabolism in a cohort of women with breast cancer treated with aromatase inhibitors. METHODS: Fifteen postmenopausal nondiabetic women were prospectively enrolled. Oral glucose tolerance test (OGTT) and metabolic parameters, including FGF21, were assessed at baseline and one month after Dmab injection. Midterm glucose control was evaluated by measuring glycated haemoglobin (HbA1c) levels 5 months after Dmab. RESULTS: Parameters of glucose metabolism were not different one month after Dmab but circulating FGF21 levels significantly decreased (128.5 ± 46.8 versus 100.2 ± 48.8 pg/mL; p=0.016). Considering patients with insulin resistance at baseline (HOMA-IR > 2.5 and Matsuda Index < 2.5; n = 5), reduced mean fasting insulin levels (16.3 ± 4.9 versus 13.5 ± 3.5 mcU/mL; p=0.029) and increased insulin sensitivity index QUICKI (0.317 ± 0.013 versus 0.327 ± 0.009; p=0.025) were found. Nonetheless, HbA1c increased 5 months after Dmab (36.0 ± 2.3 versus 39.6 ± 3.1 mmol/mol; p=0.01). CONCLUSIONS: Although RANKL blockade induced a short-term positive effect on insulin sensitivity, particularly in insulin-resistant patients, a benefit on long-term glucose metabolism was not evident. In conclusion, Dmab is safe for glucose metabolism in aromatase inhibitor-treated women with breast cancer.

Growth Hormone Therapy Does Not Increase the Risk of Craniopharyngioma and Nonfunctioning Pituitary Adenoma Recurrence.

CONTEXT: Recombinant human growth hormone (rhGH) replacement therapy is often prescribed in patients with nonfunctioning pituitary adenoma (NFPA) or craniopharyngioma. OBJECTIVE: To study whether rhGH therapy in patients with adult growth hormone deficiency (AGHD) increases the risk of pituitary tumor recurrence. DESIGN: Retrospective, observational study. SETTING: Tertiary care center. PATIENTS: We studied 283 consecutive patients with AGHD due to NFPA or craniopharyngioma between 1995 and 2018. INTERVENTION: rhGH treatment at standard doses was initiated in 123 patients (43.5%). The remaining 160 patients served as controls. MAIN OUTCOME MEASURE: Risk of tumor recurrence in rhGH-treated and control patients. RESULTS: In univariate analysis, recurrence of the pituitary tumor was less frequent in rhGH-treated patients (19.5%) than in controls (29.7%; hazard ratio [HR] 0.53, 95% confidence interval [CI] 0.32-0.86; P = .01). Multivariate Cox analysis demonstrated that the risk of tumor recurrence was associated with detection of residual disease at the baseline magnetic resonance imaging (HR 9.17; 95% CI, 4.88-17.22; P < .001) and not having performed radiotherapy (HR 16.97; 95% CI, 7.55-38.16; P < .001), while rhGH treatment was no longer associated with a lower risk of recurrence (HR 0.82; 95% CI, 0.47-1.44; P = .50). CONCLUSIONS: We found no association between rhGH replacement and the risk of tumor recurrence in patients with AGHD caused by NFPA or craniopharyngioma. These data add to the mounting evidence that rhGH therapy has a neutral effect on the recurrence of pituitary tumors. PRÉCIS: Replacement therapy with rhGH is prescribed to patients with adult growth hormone deficiency. Our study found no increased risk of pituitary tumor recurrence.

Somatostatin analog challenge test in the pre-surgical management of ACTH-secreting pheochromocytoma.

SUMMARY: ACTH-secreting pheochromocytoma is a very rare cause of Cushing's syndrome, with a high morbidity and mortality risk due to both cortisol and catecholamines excess. We report the case of a 45-year-old female patient with a 3 cm, high-density, left adrenal mass, diagnosed as an ACTH-secreting pheochromocytoma. The biochemical sensitivity of the tumor to somatostatin analogues was tested by a 100 µg s.c. octreotide administration, which led to an ACTH and cortisol reduction of 50 and 25% respectively. In addition to alpha and beta blockers, preoperative approach to laparoscopic adrenalectomy included octreotide, a somatostatin analogue, together with ketoconazole, in order to achieve an adequate pre-surgical control of cortisol release. Histopathological assessment confirmed an ACTH-secreting pheochromocytoma expressing type 2 and 5 somatostatin receptors (SSTR-2 and -5). LEARNING POINTS: ACTH-secreting pheochromocytomas represent a rare and severe condition, characterized by high morbidity and mortality risk. Surgical removal of the adrenal mass is the gold standard treatment, but adequate medical therapy is required preoperatively to improve the surgical outcome and to avoid major complications. Somatostatin analogs, in addition to other medications, may represent a useful therapeutic option for the presurgical management of selected patients. In this sense, the octreotide challenge test is a useful tool to predict favorable therapeutic response to the treatment.

Short-term evaluation of cardiac morphology, function, metabolism and structure following diagnosis of adult-onset growth hormone deficiency.

OBJECTIVE: The impact of growth hormone (GH) deficiency of the adult on cardiovascular function remains only partially elucidated. Purpose of this study was to test cardiac function in adult GH deficient patients using cardiac magnetic resonance (CMR). DESIGN: Cardiac magnetic resonance (CMR) techniques, including cardiac 31P MR spectroscopy and evaluation of gadolinium late-enhancement, were applied to assess simultaneously, in a cross-sectional fashion, morphological, functional, metabolic, and structural parameters of the left (LV) and right ventricle (RV) in 15 patients with adult onset GH deficiency. Fifteen healthy individuals served as controls. RESULTS: In GH deficient patients LV systolic function (EF%: 61 ±â€¯1.7 vs 62.1 ±â€¯0.8; p = .44) was not different in spite of a lower LV mass (83.2 ±â€¯5.3 vs 145.3 ±â€¯11.9 g; p = .001), a subclinical impairment of diastolic function (E/A peak ratio: 1.6 ±â€¯0.2 vs 2.1 ±â€¯0.2 p = .05), and a trend for lower PCr/ATP ratio (2.1 ±â€¯0.8 vs 2.3 ±â€¯0.1 p = .07). The RV showed reduced chamber size (end diastolic volume 123.8 ±â€¯9 vs 147.9 ±â€¯7.6 mL; p = .021) with preserved mass. No structural alterations of the LV and RV at late-enhancement were detected in these patients. CONCLUSIONS: GH deficient patients represent a unique model of reduced LV myocardial mass in which major structural and metabolic alterations are lacking. Mal-adaptive mechanisms developing in the long term in response to GH deficiency and more severely affecting the LV remain to be elucidated.

Topiramate pharmacokinetics in children and adults with epilepsy: a case-matched comparison based on therapeutic drug monitoring data.

OBJECTIVE: To compare the steady-state pharmacokinetics of topiramate in a large population of children and adults with epilepsy in a therapeutic drug monitoring setting. STUDY DESIGN: Retrospective, case-matched pharmacokinetic evaluation. PATIENTS: Seventy children (aged 1-17 years) with epilepsy and 70 adult controls (aged 18-65 years) with epilepsy, matched for sex and comedication. METHODS: Topiramate apparent oral clearance (CL/F) values were calculated from steady-state serum concentrations in children and compared with those determined in controls. Comparisons were made by means of the Mann-Whitney's U-test, or the Kruskal-Wallis test in the case of multiple comparisons. A linear regression model was used to assess potential correlation of CL/F values with age. To investigate the influence of different variables on the variability in topiramate CL/F values, a multiple regression model was developed. RESULTS: In the absence of enzyme-inducing comedication, mean topiramate CL/F was 42% higher in children than in adults (40.3 +/- 21.0 vs 28.4 +/- 15.3 mL/h/kg; p < 0.01). In children and adults comedicated with enzyme-inducing antiepileptic drugs (AEDs), topiramate CL/F values were approximately 1.5- to 2-fold higher than those observed in the absence of enzyme inducers, and the elevation in topiramate CL/F in children compared with adults was also present in the subgroups receiving enzyme inducers (66%; 76.6 +/- 35.1 vs 46.1 +/- 16.7 mL/h/kg; p < 0.0001). In the paediatric population, a negative correlation between CL/F and age was demonstrated, both in the absence (p < 0.01) and in the presence (p < 0.001) of enzyme induction. The independent influence of age and enzyme-inducing AEDs on topiramate CL/F was confirmed by multiple regression analysis. CONCLUSION: Topiramate CL/F is highest in young children and decreases progressively with age until puberty, presumably due to age-dependent changes in the rate of drug metabolism. As a result of this, younger patients require higher dosages to achieve serum topiramate concentrations comparable with those found in older children and adults. Enzyme-inducing comedication decreases serum topiramate concentration by approximately one-half and one-third in children and adults, respectively.

Treatment of thyroid-associated orbitopathy with rituximab--a novel therapy for an old disease: case report and literature review.

OBJECTIVE: To report the use of rituximab to treat thyroid-associated orbitopathy (TAO) in a patient with a concomitant B-cell organ-specific autoimmune disorder-the stiff person syndrome (SPS). METHODS: We present a case report and a review of the related literature. RESULTS: A 62-year-old man with SPS, latent autoimmune diabetes of the adult, and Graves-Basedow disease was referred to our medical center because of bilateral TAO. An ophthalmologic examination documented asymmetric bilateral NOSPECS (N = no signs or symptoms; O = only signs, no symptoms; S = soft tissue involvement; P = proptosis; E = extraocular muscle involvement; C = corneal involvement; and S = sight loss) class IV TAO (left eye>right eye) with a clinical activity score of 5 on a scale of 7. Magnetic resonance imaging of the orbits documented bilateral exophthalmos (left eye>right eye) due to retrobulbar fibroadipose infiltration, bilateral increase of extrinsic ocular muscle thickness, and enhancement of the left inferior rectus muscle on T2-weighted sequences. Because of concomitant incapacitating SPS and diet-controlled latent autoimmune diabetes of the adult, we excluded long-term corticosteroid therapy as an option and considered the use of rituximab, a mouse-human chimeric monoclonal antibody targeting the CD20 protein on pre-B and mature B lymphocytes. Rituximab was administered in accordance with the protocol for rheumatoid arthritis. During the subsequent 4 months, clinical signs and symptoms of TAO dramatically resolved (clinical activity score = 0 of 7) with a sustained improvement of the spastic paraparesis. The glutamic acid decarboxylase antibody titer remained high, and glycemic control and first-phase insulin secretion did not change. CONCLUSION: Treatment of active TAO with rituximab should be considered when standard intravenous pulse glucocorticoid treatment is contraindicated or ineffective and when SPS or other organ-specific autoimmune disorders with involvement of humoral autoimmunity are present, inasmuch as more than 1 disease may benefit from the use of this chimeric monoclonal antibody.

Long-term effects of growth hormone replacement therapy on thyroid function in adults with growth hormone deficiency.

BACKGROUND: Clinical studies on the effect of growth hormone (GH) on thyroid function in patients with GH deficiency are contradictory. Further, the majority of published observations are limited to the first 6-12 months of GH replacement therapy. The aim of our study was to estimate the incidence of clinically relevant hypothyroidism in a cohort of patients with adult GH deficiency (AGHD) during long-term therapy with recombinant human GH (rhGH). METHODS: The study was designed as a retrospective collection of data on thyroid function in 49 AGHD patients of whom 44 (90%) had multiple hormone deficiency. Thirty-seven patients (76%) were on stable levothyroxine (LT4) replacement therapy (HYPO), and 12 (24%) were euthyroid (EUT). Therapy with rhGH was started at a dose of 3.5 microg/kg body weight and adjusted according to insulin-like growth factor-I (IGF-I) levels. At baseline, 6 months, 12 months, and yearly thereafter we measured free triiodothyronine (fT3), free thyroxine (fT4), thyroid-stimulating hormone, and IGF-I. Study outcome was fT4 level below the normal range (9 pmol/L), irrespectively of fT3 or thyroid-stimulating hormone levels. RESULTS: During a follow-up of 115 patient-years, mean fT4 level decreased significantly, although remaining within the normal range (p = 0.0242; month 48 vs. baseline). The largest decrease was between baseline and month 6, when fT4 decreased of 1.43 pmol/L (95% confidence interval, 0.33-2.53) per 1 unit (microg/kg body weight) increase in rhGH dose. The incidence of hypothyroidism was 1.2 (HYPO group) and 6.7 (EUT group) events per 100 patient-years. CONCLUSION: We confirm that in patients with AGHD, rhGH therapy is associated with a small, although significant, decrement of fT4 in the first 6 months of replacement therapy. However, the incidence of hypothyroidism is low. Monitoring of thyroid function during rhGH therapy is advisable, particularly in the first year of therapy when the largest decrease in fT4 occurs.

Serum carbamazepine concentrations in elderly patients: a case-matched pharmacokinetic evaluation based on therapeutic drug monitoring data.

PURPOSE: To assess the influence of aging on the steady-state pharmacokinetics of carbamazepine (CBZ) in a large population of patients evaluated in a therapeutic drug monitoring (TDM) setting. METHODS: The database of a large TDM service was used to identify retrospectively steady-state serum CBZ concentrations in 157 elderly patients with epilepsy (65 years and older) treated with CBZ alone or in combination with phenobarbital (PB). CBZ apparent oral clearance (CL/F) values were calculated and compared with those determined in an equal number of controls aged 20 to 50 years, and matched for gender, body weight, and comedication. RESULTS: Compared with corresponding controls, mean CBZ CL/F values were 23% and 24% lower, respectively, in the groups of elderly patients receiving monotherapy (57.1 +/- 20.6 vs. 74.6 +/- 28.3 ml/h/kg; p < 0.0001) and PB comedication (74.7 +/- 25.5 vs. 98.7 +/- 34.9 ml/h/kg; p < 0.01). Within each age group, patients comedicated with PB showed significantly higher CBZ CL/F values than those on monotherapy. A negative correlation between CL/F and age was found both within the monotherapy and the PB comedicated groups. In addition, CL/F values showed a positive relation with the administered daily dosage, which persisted within subgroups homogeneous for age and comedication. The independent influence of age, CBZ dosage, and comedication on CBZ CL/F was confirmed by multiple regression analysis. CONCLUSIONS: CBZ CL/F is decreased in an age-dependent manner in elderly patients compared with younger subjects, presumably because a reduction in the rate of CYP3A4-mediated drug metabolism. Elderly patients retain their sensitivity to dose-dependent autoinduction and to heteroinduction by enzyme-inducing AEDs, but their metabolic rates remain considerably below those observed in matched controls. As a result of this, patients in old age will require lower CBZ dosages to achieve serum concentrations comparable with those found in nonelderly adults.