Hanan A. Tanash

Clinical course and prognosis of never-smokers with severe alpha-1-antitrypsin deficiency (PiZZ)

Background: Previous studies of non-smoking individuals with severe α1-antitrypsin deficiency (PiZZ) have been sparse and included only a limited number of individuals, mostly identified by respiratory symptoms. The aim of this study was to estimate the prognosis of non-smoking PiZZ individuals and to analyse the most common causes of death by including a large number of individuals who had been identified by other means than respiratory symptoms. Methods: The study included 568 non-smoking PiZZ subjects who were selected from the Swedish National AAT Deficiency Registry and followed up from 1991 to September 2007. Of these, 156 (27%) were identified by respiratory symptoms (respiratory cases) and 412 were identified by extrapulmonary symptoms or screening (non-respiratory cases). Results: 93 subjects (16%) died during the follow-up period. The specific standardised mortality rate (SMR) for the whole study population was 2.32 (95% CI 1.87 to 2.83) with no significant difference between men and women. The SMR was 2.55 (95% CI 1.91 to 2.83) for the respiratory cases and 2.07 (95% CI 1.49 to 2.81) for the non-respiratory cases. Further calculation of SMR for subgroups in the non-respiratory cases showed that the SMR was 0.70 (95% CI 0.14 to 2.04) for individuals identified by family/population screening. Emphysema and liver cirrhosis were the most common causes of death (45% and 28%, respectively). Malignant transformation was found in 38% of the cases with cirrhosis. Conclusion: Non-smoking PiZZ individuals identified by screening do not have an increased mortality risk compared with the Swedish general population.

Survival in severe alpha-1-antitrypsin deficiency (PiZZ)

BackgroundPrevious studies of the natural history of alpha-1-antitrypsin (AAT) deficiency are mostly based on highly selected patients. The aim of this study was to analyse the mortality of PiZZ individuals.MethodsData from 1339 adult PiZZ individuals from the Swedish National AAT Deficiency Registry, followed from 1991 to 2008, were analysed. Forty-three percent of these individuals were identified by respiratory symptoms (respiratory cases), 32% by liver diseases and other diseases (non-respiratory cases) and 25% by screening (screened cases). Smoking status was divided into two groups: smokers 737 (55%) and 602 (45%) never-smokers.ResultsDuring the follow-up 315 individuals (24%) died. The standardised mortality rate (SMR) for respiratory cases was 4.70 (95% Confidence Interval (CI) 4.10-5.40), 3.0 (95%CI 2.35-3.70) for the non-respiratory cases and 2.30 (95% CI 1.46-3.46) for the screened cases. The smokers had a higher mortality risk than never-smokers, with a SMR of 4.80 (95%CI 4.20-5.50) for the smokers and 2.80(95%CI 2.30-3.40) for the never-smokers. The Rate Ratio (RR) was 1.70 (95% CI 1.35-2.20). Also among the screened cases, the mortality risk for the smokers was significantly higher than in the general Swedish population (SMR 3.40 (95% CI 1.98-5.40).ConclusionSmokers with severe AAT deficiency, irrespective of mode of identification, have a significantly higher mortality risk than the general Swedish population.

Survival benefit of lung transplantation in individuals with severe α1-anti-trypsin deficiency (PiZZ) and emphysema

BACKGROUND The objective of lung transplantation (LTx) is to prolong life, but the survival benefit for patients with severe α(1)-anti-trypsin deficiency (PiZZ) and emphysema is still unclear. The aim of this study was to assess whether PiZZ patients who have undergone lung transplantation (the lung transplant group, TxG) do better than patients who have continued on the usual medical therapy (the non-transplant group, NTxG). METHODS Between 1990, when the first patient received a lung transplant in Sweden, until June 2010, a total of 83 PiZZ patients with severe emphysema underwent transplantation. Seventy appropriate controls were identified from the Swedish National AAT Deficiency Registry. Each control was matched with a patient who had received a lung transplant, for age, gender, smoking history (number of pack-years) and lung function at the time of transplantation. RESULTS Both controls and lung transplant patients had low spirometric values with a mean FEV(1) of 23 ± 6% and 22 ± 9% of predicted value, respectively (not a statistically significant difference). Of the 83 transplant patients, 62 (75%) underwent single-lung transplantation (SLTx). During follow-up, 37 (45%) deaths occurred in the TxG and 45 (64%) in the NTxG. In the TxG, the estimated median survival time was 11 years (95% confidence interval [CI] 9 to 14 years), compared with 5 years (95% CI 4 to 6 years) for the NTxG (p = 0.006). The most common cause of death was pulmonary infection among the transplant patients (38%) and respiratory failure (60%) among the controls. CONCLUSION Lung transplantation significantly improves long-term survival of patients with severe α(1)-anti-trypsin deficiency (PiZZ) and emphysema.

The Swedish Alpha 1-antitrypsin Screening Study: Health Status, Lung and Liver Function at Age 34.

RATIONALE All Swedish newborn infants were screened for α1-antitrypsin (AAT) deficiency between 1972 and 1974. The cohort of 127 individuals with severe AAT deficiency (PiZZ) and 54 with moderate AAT deficiency (PiSZ) has been followed up regularly. OBJECTIVES To compare smoking habits, quality of life, respiratory symptoms, and lung and liver function at the age of 34 years in this cohort and among 300 age-matched control subjects randomly selected from the Swedish population registry. METHODS The study participants answered a questionnaire on smoking habits and symptoms; underwent spirometry, including FEV1 and FVC; and provided blood samples. Health-related quality of life was assessed by using the St. Georges Respiratory Questionnaire (SGRQ). MEASUREMENTS AND MAIN RESULTS One hundred sixteen PiZZ, 48 PiSZ, and 229 control subjects (normal AAT level [PiMM]) answered the questionnaire. Eighty-eight PiZZ (76%), 36 PiSZ (75%), and 144 PiMM (63%) subjects had never smoked (P = 0.02). No significant differences were found in lung function parameters between the protease inhibitor (Pi) subgroups, nor were any discovered between the smoking subgroups. In all Pi subgroups, the symptom score on the SGRQ was significantly lower in ever-smokers than in never-smokers (P = 0.01 for PiZZ, P = 0.009 for PiSZ, and P = 0.01 for PiMM). The mean plasma levels of liver enzymes and albumin were within normal range in all Pi subgroups. However, the mean γ-glutamyl transpeptidase and albumin levels were significantly higher in the PiZZ than in the PiMM subjects (P < 0.05). CONCLUSIONS In this population-based study, no differences in lung function or symptoms were found between subjects with AAT deficiency and control subjects, but smoking frequency was significantly lower among the subjects with AAT deficiency than in the controls at age 34 years.

Lung Function and CT Densitometry in Subjects with alpha-1-Antitrypsin Deficiency and Healthy Controls at 35 Years of Age.

Abstract Alpha-1-antitrypsin (AAT) deficiency is a genetic risk factor for pulmonary emphysema. In 1972–74 all 200,000 Swedish new-born infants were screened for AAT deficiency. The aim of the present study was to investigate whether the PiZZ and PiSZ individuals identified by this screening have signs of emphysema and the role of smoking in this, compared with a random sample of control subjects at 35 years of age. The study participants underwent complete pulmonary function tests (PFT) and CT densitometry. The fifteenth percentile density (PD15) and the relative area below –910 HU (RA–910) were analyzed. Fifty-four PiZZ, 21 PiSZ and 66 PiMM control subjects participated in the study. No significant differences were found in lung function between the never-smoking AAT-deficient and control subjects. The 16 PiZZ ever-smokers had significantly lower carbon monoxide transfer coefficient (KCO) than the 20 PiSZ never-smokers (p = 0.014) and the 44 PiMM never-smokers (p = 0.005). After correction for the CT derived lung volume, the PiZZ ever-smokers had significantly lower PD15 (p = 0.046) than the ever-smoking controls. We conclude that 35-year-old PiZZ and PiSZ never-smokers have normal lung function when compared with never-smoking control subjects. The differences in KCO and CT densitometric parameters between the PiZZ ever-smokers and the control subjects may indicate early signs of emphysema.

The Clinical Profile of Subjects Included in the Swedish National Register on Individuals with Severe Alpha 1-Antitrypsin deficiency.

Abstract The Swedish national register of severe alpha1-antitrypsin (AAT) deficiency was established in 1991. The main aims are to prospectively study the natural history of severe AAT deficiency, and to improve the knowledge of AAT deficiency. The inclusion criteria in the register are age ≥18 years, and the PiZ phenotype diagnosed by isoelectric focusing. The register is kept updated by means of repeated questionnaires providing data to allow analysis of the mode of identification, lung and liver function, smoking-habits, respiratory symptoms and diagnoses as reported by physicians. Until February 2014, a total of 1553 PiZZ individuals had been included in the register. The 1102 subjects still alive constituted about 20% of the adult PiZZ individuals in Sweden. Forty-three percent of the subjects had been identified during investigation of respiratory symptoms, 7% by an investigation of liver disease, 26% in an investigation of other pathological conditions, and 24% in a population or family screening. Forty five percent of the subjects had never smoked, 47% were ex-smokers, and 8% current smokers. Twenty-eight percent of the never-smokers, 72% of the ex-smokers, and 61% of the current smokers fulfilled the criteria for COPD with a FEV1/FVC ratio of <0.70. Among the 451 deceased, the most common cause of death was respiratory diseases (55%), followed by liver diseases (13%). We conclude that the detection rate of severe AAT deficiency is relatively high in Sweden. Large numbers of subjects are identified for other reasons than respiratory symptoms, and the majority of these have never smoked.

Liver function in alpha-1-antitrypsin deficient individuals at 37 to 40 years of age

Abstract Severe alpha-1-antitrypsin (AAT) deficiency (PiZZ) is a risk factor for liver disease, but the prevalence of liver cirrhosis and hepatocellular cancer in PiZZ adults is unknown. The risk of liver disease in adults with moderate AAT deficiency (PiSZ) is also unknown. A cohort of 127 PiZZ, 2 PiZnull, 54 PiSZ, and 1 PiSnull individuals were identified by the Swedish national neonatal AAT screening program between 1972 and 1974, when all 200,000 newborn infants in Sweden were screened for AAT deficiency. The cohort has been followed up since birth. Our aim was to study liver function and signs of liver disease in this cohort at 37 to 40 years of age in comparison with a matched, random sample of control subjects identified from the population registry. Eighty seven PiZZ, 32 PiSZ, and 92 control subjects (PiMM) answered a questionnaire on medication and alcohol consumption and provided blood samples. Liver stiffness was assessed by Acoustic Radiation Force Impulse (ARFI) elastography in 32 PiZZ, 15 PiSZ, and 51 PiMM subjects. The median of liver function tests and procollagen-III-peptide were within the normal range in all Pi subgroups. However, the PiZZ men had significantly higher plasma bilirubin than the PiMM men (P = 0.018). Plasma [Latin Small Letter Gamma]-glutamyl transferase (GGT) was significantly higher in the PiZZ men (P = 0.009) and the PiSZ men (P = 0.021) compared with the PiMM men. The median of liver stiffness was significantly higher in the PiZZ men (P = 0.037) and the PiSZ men (P = 0.032) compared with the PiMM men. The PiZZ women taking medication influencing liver enzymes had significantly higher GGT than the PiMM women on the corresponding treatment (P = 0.023). These AAT-deficient individuals identified by neonatal screening have normal plasma levels of liver function tests, and no clinical signs indicating liver disease at the age of 37 to 40 years. However, bilirubin, GGT, and liver stiffness are significantly higher in PiZZ men than PiMM men.

Cause-specific mortality in individuals with severe alpha 1-antitrypsin deficiency in comparison with the general population in Sweden

Background Severe alpha 1-antitrypsin deficiency (PiZZ) predisposes to morbidity and mortality due to early-onset emphysema and liver disease. The risk of death from other causes, including cardiovascular disease and cancer, has not been well investigated. We aimed to analyze cause-specific mortality in PiZZ individuals compared with the general Swedish population. Methods Data on 1,561 PiZZ individuals from the Swedish National AAT Deficiency Register, prospectively followed from 1991 to 2014, were analyzed. Causes of death according to the Swedish National Causes of Death Register for the study group were compared with those for the general Swedish population matched for age, sex, and calendar year, with the excess mortality expressed as standardized mortality ratios (SMRs) with 95% confidence intervals (CIs). Results There were 524 deaths during the follow-up period. PiZZ individuals had excess all-cause mortality compared with the Swedish general population (SMR 3.6, 95% CI 3.3–3.9). SMR for ischemic heart disease (IHD) was 0.5 (95% CI 0.3–0.8) and was similar for never and ever-smokers, and in males and females. SMR for lung cancer was 0.9 (95% CI 0.4–1.7). PiZZ individuals had increased mortality compared with the general population for the following diseases: respiratory disease, SMR 48.4 (95% CI 43.0–54.5); primary liver carcinoma, SMR 90.0 (95% CI 59.3–130.9); complicated colon diverticulitis, SMR 20.8 (95% CI 6.7–48.6); and pulmonary embolism, SMR 6.9 (95% CI 3.3–12.7). Conclusion PiZZ individuals had a reduced mortality risk of IHD. Mortality due to respiratory, hepatic disease, diverticulitis, and pulmonary embolism was markedly increased compared with the age- and sex-matched Swedish population.

Health status and lung function in the Swedish alpha 1-antitrypsin deficient cohort, identified by neonatal screening, at the age of 37-40 years

Background Severe alpha 1-antitrypsin (AAT) deficiency (genotype PiZZ) is a well-known risk factor for COPD. A cohort of PiZZ and PiSZ individuals was identified by the Swedish national neonatal AAT screening program in 1972–1974 and followed up regularly since birth. Our aim was to study the lung function, respiratory symptoms and health status at the age of 38 years in comparison with a random sample of control subjects selected from the population registry. Methods The study group included 120 PiZZ, 46 PiSZ and 164 control subjects (PiMM), who answered a questionnaire on smoking habits and symptoms and the Saint George Respiratory Questionnaire (SGRQ) on quality of life. A total of 89 PiZZ, 33 PiSZ and 92 PiMM subjects underwent spirometry. Results Four percent of the PiZZ, 2% of the PiSZ and 12% of the control subjects were current smokers (P=0.008), and 17% of the PiZZ, 9% of the PiSZ and 21% of the control subjects had stopped smoking. The PiZZ current smokers had a significantly higher (ie, poorer) median activity score according to the SGRQ than the PiZZ never-smokers (P=0.032). The PiMM current smokers had significantly higher activity score (P<0.001), symptom score (P<0.001), and total score (P=0.001) according to the SGRQ than the PiMM never-smokers. The PiZZ current smokers had a significantly lower postbronchodilator forced expiratory volume in 1 second (FEV1)% of predicted value (P=0.019) and FEV1/forced vital capacity (FVC) ratio (P=0.032) than the PiZZ never-smokers. The proportion of subjects with a FEV1/FVC ratio of <0.70, indicating COPD, was significantly higher in the PiZZ current smokers than in the PiZZ never-smokers (P=0.001). Among the PiSZ and PiMM subjects, the differences in lung function between the smoking subgroups were insignificant. Conclusion PiZZ current smokers were found to have signs of COPD before 40 years of age. Smoking is less common among the AAT-deficient subjects identified by neonatal screening than among their peers in the general population.

The risk of burn injury during long-term oxygen therapy: a 17-year longitudinal national study in Sweden.

Background Long-term oxygen therapy (LTOT) improves the survival time in hypoxemic chronic obstructive pulmonary disease. Despite warnings about potential dangers, a considerable number of patients continue to smoke while on LTOT. The incidence of burn injuries related to LTOT is unknown. The aim of this study was to estimate the rate of burn injury requiring health care contact during LTOT. Methods Prospective, population-based, consecutive cohort study of people starting LTOT from any cause between January 1, 1992 and December 31, 2009 in the Swedish National Register of Respiratory Failure (Swedevox). Results In total, 12,497 patients (53% women) were included. The mean (standard deviation) age was 72±9 years. The main reasons for starting LTOT were chronic obstructive pulmonary disease (75%) and pulmonary fibrosis (15%). Only 269 (2%) were active smokers when LTOT was initiated. The median follow-up time to event was 1.5 years (interquartile range, 0.55–3.1). In total, 17 patients had a diagnosed burn injury during 27,890 person-years of LTOT. The rate of burn injury was 61 (95% confidence interval, 36–98) per 100,000 person-years. There was no statistically significant difference in the rate of burn injury between ever-smokers and never-smokers, or between men and women. Conclusion The rate of burn injuries in patients on LTOT seems to be low in Sweden. The strict requirements in Sweden for smoking cessation before LTOT initiation may contribute to this finding.