Ingunn Hansdottir

A Variant Associated with Nicotine Dependence, Lung Cancer and Peripheral Arterial Disease

Smoking is a leading cause of preventable death, causing about 5 million premature deaths worldwide each year. Evidence for genetic influence on smoking behaviour and nicotine dependence (ND) has prompted a search for susceptibility genes. Furthermore, assessing the impact of sequence variants on smoking-related diseases is important to public health. Smoking is the major risk factor for lung cancer (LC) and is one of the main risk factors for peripheral arterial disease (PAD). Here we identify a common variant in the nicotinic acetylcholine receptor gene cluster on chromosome 15q24 with an effect on smoking quantity, ND and the risk of two smoking-related diseases in populations of European descent. The variant has an effect on the number of cigarettes smoked per day in our sample of smokers. The same variant was associated with ND in a previous genome-wide association study that used low-quantity smokers as controls, and with a similar approach we observe a highly significant association with ND. A comparison of cases of LC and PAD with population controls each showed that the variant confers risk of LC and PAD. The findings provide a case study of a gene–environment interaction, highlighting the role of nicotine addiction in the pathology of other serious diseases.

The relationship between physical appearance concerns, disgust, and anti-fat prejudice

This study examined relationships between physical appearance concerns (fear of fat, body image disturbance; BIDQ), disgust, and anti-fat prejudice (dislike, blame), and tested whether disgust mediates relationships between physical appearance concerns and anti-fat prejudice. Participants (N=1649; age=28 years) provided demographic data and completed measures of anti-fat prejudice, tendency to feel disgust, and physical appearance concerns. Univariate, multivariate, and mediation analyses were conducted. Univariate and multivariate associations were found between fear of fat, BIDQ, disgust, and anti-fat prejudice for women. For women only, mediation analyses showed that disgust partially mediated relationships between physical appearance concerns and dislike of fat people. For men, univariate and multivariate relationships were found between fear of fat, and dislike and blame of fat people, but disgust was not related to anti-fat prejudice. Newer constructs centering on physical appearance concerns and disgust appear promising candidates for understanding anti-fat prejudice.

Addictions and their familiality in Iceland

Here, we provide an overview of previous family studies of addiction and present a new family study based on clinical data for more than 19,000 individuals who have been treated for addiction in Iceland over the last three decades. Coupled with the extensive Icelandic genealogy information, this population‐based sample provides a unique opportunity for family studies. The relative risk (RR) was determined for up to fifth‐degree relatives of probands diagnosed with alcohol, cannabis, sedative, and amphetamine dependence. We observe highly significant RR values for all substances ranging from 2.27 for alcohol to 7.3 for amphetamine, for first‐degree relatives, and RRs significantly above 1 for distant relations, where the effect of shared environmental factors is minimized. The magnitude of risk in psychostimulant dependence is particularly striking. These findings emphasize the role of genetics in the etiology of addiction and highlight the importance of substance‐specific effects.

Posttraumatic stress and other health consequences of catastrophic avalanches: A 16-year follow-up of survivors

To date, no study has investigated the effects of avalanches on survivors health beyond the first years. The aim of this study was to examine long-term health status 16 years after exposure to avalanches using a matched cohort design. Mental health, sleep quality and somatic symptoms among avalanche survivors (n=286) and non-exposed controls (n=357) were examined. Results showed that 16% of survivors currently experience avalanche-specific PTSD symptoms (PDS score>14). In addition, survivors presented with increased risk of PTSD hyperarousal symptoms (>85th percentile) (aRR=1.83; 98.3% CI [1.23-2.74]); sleep-related problems (PSQI score>5) (aRR=1.34; 95% CI [1.05-1.70]); PTSD-related sleep disturbances (PSQI-A score≥4) (aRR=1.86; 95% CI [1.30-2.67]); musculoskeletal and nervous system problems (aRR 1.43; 99% CI 1.06-1.93) and gastrointestinal problems (aRR 2.16; 99% CI 1.21-3.86) compared to the unexposed group. Results highlight the need for treatment for long-term PTSD symptoms and sleep disruption in disaster communities.

Polygenic risk scores for schizophrenia and bipolar disorder associate with addiction

We use polygenic risk scores (PRSs) for schizophrenia (SCZ) and bipolar disorder (BPD) to predict smoking, and addiction to nicotine, alcohol or drugs in individuals not diagnosed with psychotic disorders. Using PRSs for 144 609 subjects, including 10 036 individuals admitted for in‐patient addiction treatment and 35 754 smokers, we find that diagnoses of various substance use disorders and smoking associate strongly with PRSs for SCZ (P = 5.3 × 10−50–1.4 × 10−6) and BPD (P = 1.7 × 10−9–1.9 × 10−3), showing shared genetic etiology between psychosis and addiction. Using standardized scores for SCZ and BPD scaled to a unit increase doubling the risk of the corresponding disorder, the odds ratios for alcohol and substance use disorders range from 1.19 to 1.31 for the SCZ‐PRS, and from 1.07 to 1.29 for the BPD‐PRS. Furthermore, we show that as regular smoking becomes more stigmatized and less prevalent, these biological risk factors gain importance as determinants of the behavior.

The Adult Reading History Questionnaire (ARHQ) in Icelandic: Psychometric Properties and Factor Structure

This article describes psychometric testing of an Icelandic adaptation of the Adult Reading History Questionnaire (ARHQ), designed to detect a history of reading difficulties indicative of dyslexia. Tested in a large and diverse sample of 2,187 adults, the Icelandic adaptation demonstrated internal consistency reliability (Cronbach’s alpha = .92) and test–retest reliability (r = .93). Validity was established by comparing scores of adults who as children received ICD-10 diagnoses of specific reading disorder (F81.0; n = 419) to those of adults defined as nondyslexics (n = 679). ROC curve analysis resulted in an area under the curve of .92 (95% CI = .90, .93, p < .001) and a cutoff score of .43 with sensitivity of 84.5% and specificity of 83.7%. An exploratory factor analysis (n = 2,187) suggested three subscales, Dyslexia Symptoms, Current Reading, and Memory, the mean scores of which differed significantly among diagnosed dyslexics, relatives of dyslexics, and population controls. Our results support the applicability of the ARHQ in Icelandic as a self-report screening tool for adult dyslexia in Iceland.

The effects of instructions and anxiety on interrogative suggestibility

Abstract This study investigates the effects of instructional manipulation and anxiety manipulation on interrogative suggestibility by using a 2 × 2 experimental design. There were 40 subjects, divided into four groups. The results show that both instructional and anxiety manipulation significantly affect suggestibility within an experimental context. The findings are interpreted within the theoretical framework of Gudjonsson & Clark ( Social Behavior , 1 , 83–104, 1986).

Modelling the elimination of hepatitis C as a public health threat in Iceland: A goal attainable by 2020.

BACKGROUND & AIMS In Iceland a nationwide program has been launched offering direct-acting antiviral (DAA) treatment for everyone living with hepatitis C virus (HCV). We estimate (i) the time and treatment scale-up required to achieve the World Health Organizations HCV elimination target of an 80% reduction in incidence; and (ii) the ongoing frequency of HCV testing and harm reduction coverage among people who inject drugs (PWID) required to minimize the likelihood of future HCV outbreaks occurring. METHODS We used a dynamic compartmental model of HCV transmission, liver disease progression and the HCV cascade of care, calibrated to reproduce the epidemic of HCV in Iceland. The model was stratified according to injecting drug use status, age and stage of engagement. Four scenarios were considered for the projections. RESULTS The model estimated that an 80% reduction in domestic HCV incidence was achievable by 2030, 2025 or 2020 if a minimum of 55/1,000, 75/1,000 and 188/1,000 PWID were treated per year, respectively (a total of 22, 30 and 75 of the estimated 400 PWID in Iceland per year, respectively). Regardless of time frame, this required an increased number of PWID to be diagnosed to generate enough treatment demand, or a 20% scale-up of harm reduction services to complement treatment-as-prevention incidence reductions. When DAA scale-up was combined with annual antibody testing of PWID, the incidence reduction target was reached by 2024. Treatment scale-up with no other changes to current testing and harm reduction services reduced the basic reproduction number of HCV from 1.08 to 0.59, indicating that future outbreaks would be unlikely. CONCLUSION HCV elimination in Iceland is achievable by 2020 with some additional screening of PWID. Maintaining current monitoring and harm reduction services while providing ongoing access to DAA therapy for people diagnosed with HCV would ensure that outbreaks are unlikely to occur once elimination targets have been reached. LAY SUMMARY In Iceland, a nationwide program has been launched offering treatment for the entire population living with hepatitis C virus (HCV). A mathematical model was used to estimate the additional health system requirements to achieve the HCV elimination targets of the World Health Organization (WHO), as well as the year that this could occur. With some additional screening of people who inject drugs, Iceland could reach the WHO targets by 2020, becoming one of the first countries to achieve HCV elimination. The model estimated that once elimination targets were reached, maintaining current monitoring and harm reduction services while providing ongoing access to DAA therapy for people diagnosed with HCV would ensure that future HCV outbreaks are unlikely to occur.

Treatment as Prevention for Hepatitis C (TraP Hep C) – a nationwide elimination programme in Iceland using direct-acting antiviral agents

A nationwide programme for the treatment of all patients infected with hepatitis C virus (HCV) was launched in Iceland in January 2016. By providing universal access to direct‐acting antiviral agents to the entire patient population, the two key aims of the project were to (i) offer a cure to patients and thus reduce the long‐term sequelae of chronic hepatitis C, and (ii) to reduce domestic incidence of HCV in the population by 80% prior to the WHO goal of HCV elimination by the year 2030. An important part of the programme is that vast majority of cases will be treated within 36 months from the launch of the project, during 2016–2018. Emphasis is placed on early case finding and treatment of patients at high risk for transmitting HCV, that is people who inject drugs (PWID), as well as patients with advanced liver disease. In addition to treatment scale‐up, the project also entails intensification of harm reduction efforts, improved access to diagnostic tests, as well as educational campaigns to curtail spread, facilitate early detection and improve linkage to care. With these efforts, Iceland is anticipated to achieve the WHO hepatitis C elimination goals well before 2030. This article describes the background and organization of this project. Clinical trial number: NCT02647879.

Extended-release Injectable Naltrexone (xr-ntx) With Intensive Psychosocial Therapy for Amphetamine-dependent Persons Seeking Treatment: A Placebo-controlled Trial

Objective: Explore the efficacy of extended-release injectable naltrexone (XR-NTX) for preventing relapse to amphetamine use. Method: Clinical trial of 100 amphetamine-dependent, treatment-seeking patients who were randomized to 6 monthly 380 mg doses of XR-NTX or matching placebo before entering intensive outpatient after varying lengths of inpatient treatment in Reykjavik, Iceland. Weekly urine drug tests, retention, and standardized instruments assessed efficacy. Results: Of 169 approached, 100 were randomized. Although amphetamine dependence was the main reason for seeking treatment, three-quarters or more of participants had 1 or more other substance dependencies. Of 51 randomized to XR-NTX, 20 received 4 or more injections; of 49 assigned to placebo, 26 received 4 or more injections. Of the planned 2400 weekly urine drug tests, 1247 were collected (52%); 4% of these were positive for amphetamine, 8% for benzodiazepine, 7% for marijuana, 1% for cocaine, and 1% for opioid. XR-NTX had no effect on amphetamine-positive tests, retention, or other outcomes. Those providing half or more of their tests attended more weeks of treatment than those providing less than half of their tests (m = 10.76 vs 3.31; t (92) = 5.91, P < 0.0001), and 92 participants provided at least 1 test. Conclusions: Adding XR-NTX to the usual combination of inpatient and intensive outpatient treatment did not reduce amphetamine use. The low prevalence of substance use among collected urine samples, and the association between collected samples and weeks in treatment, was consistent with other studies showing that staying in treatment is associated with better outcomes.