| Sažetak | Recentne studije bilježe porast problema mentalnog zdravlja studenata u posljednjem desetljeću uz naglasak njihove povezanosti s kvalitetom sna. Kvaliteta sna dosljedno je povezana s anksioznosti, no smjer i podloga te povezanosti nisu dovoljno istraženi. Kognitivni model insomnije, Neuropatološki model i Model insomnije temeljen na prekomjernoj pobuđenosti prepoznaju ruminaciju, brigu i emocionalnu regulaciju kao važne procese u nastanku insomnije. Ovo doktorsko istraživanje provedeno je s ciljem provjere jesu li teorijske postavke spomenutih modela primjenjive na objašnjenje procesa u pozadini narušene kvalitete spavanja nekliničke populacije studenata u periodu nadolazeće odraslosti. Prikupljeni su longitudinalni podaci iz dva vala istraživanja tijekom akademske godine 2021/2022. Uzorak se sastojao od 302 studenta, pretežno ženskog spola (78.9%) u dobi od 18 do 25 godina (M=20.08, sd=1.14) s različitih fakulteta Sveučilišta u Zagrebu. Uzorkovanje je bilo prigodno radi ograničenja provedbe istraživanja u okolnostima pandemije COVID-19. Za operacionalizaciju istraživačkih konstrukata korištene su skale DASS-21 (Lovibond i Lovibond, 1995), PSQI (Buysse i sur., 1989), ECQ-R (Roger i Najarian, 1989), PSWQ (Meyer i sur., 1990), DERS (Graz i Roemer, 2004) te CSM (Smith i sur., 1989). Obrada podataka provedena je CLPM analizama zasebno za svaki od pretpostavljenih medijatora. Rezultati su pokazali da u ovom istraživanju anksioznost prethodi kvaliteti sna, ali ta veza nije recipročna. U modelima s brigom i ruminacijom kao medijatorima utvrđen je samo izravni učinak anksioznosti na kvalitetu sna. U modelu s emocionalnom regulacijom kao medijatorom utvrđena je potpuna medijacija, odnosno emocionalna regulacija u potpunosti posreduje vezi anksioznosti i kvalitete sna. Rezultati nude doprinos prevencijskoj znanosti u vidu smjernica za planiranje intervencija i preventivnih aktivnosti, ali i kroz epidemiološke podatke, provjeru teorija te smjernice za buduća istraživanja. |
| Sažetak (engleski) | Recent studies have shown an increase in students' mental health problems in the last decade. Studies indicate an increase in symptoms of anxiety, depression and stress, as well as an impaired quality of sleep among students. There are not many studies that deal with the relationship between sleep quality and anxiety in a healthy population, and especially not during transitional period to adulthood. Emerging adulthood is marked by biological, cognitive and social changes which make it an ideal period for applying various preventive activities and activities for mental health improvement. In order to successfully provide these activities, it is necessary to investigate in more detail the background of mental health problems in that specific developmental stage.
Sleep quality is consistently related to anxiety, but the direction and background of this relationship have not been sufficiently investigated. The Cognitive Model of Insomnia (Harvey, 2002), The Neuropathological Model (Goldstein et al., 2013) and the The Hyperarousal Model of Insomnia (Riemann et al., 2010) recognize rumination, worry and emotional regulation as important processes in the development and maintenance of insomnia. The Cognitive Model of Insomnia recognizes rumination and worry as cognitive processes that contribute to the maintenance of sleep problems, and these processes are also related to the appearance of anxiety. The Neuropathological Model points out that sleep disturbances can contribute to anxiety by maintaining or worsening cognitive processes, such as rumination and worry. Cognitive arousal caused by rumination and worry during the day can be extended to the period before sleep and lead to sleep problems, and unpleasant intrusive and repetitive thoughts can contribute to the development of anxiety. According to the The Hyperarousal Model of Insomnia the emotional arousal is also one of the pathways that can mediate the relationship between anxiety and sleep quality.
This doctoral research was conducted with the aim of verifying whether the theoretical assumptions of previously mentioned models are applicable to the explanation of the processes behind the impaired sleep quality of the non-clinical student population in the period of emerging adulthood. The research also offers valuable knowledge about anxiety and sleeping habits of students during the academic year. The research was conducted in paper-pencil form. Longitudinal data of two research waves were collected during winter semester and summer semester of the academic year 2021/2022. After matching the collected data, the final sample included 302 students, predominantly female (78.9%) aged from 18 to 25 (M=20.08, sd=1.14) from various faculties of the University of Zagreb. Contrary to initial plan, sample is convenient due to the limitations of conducting research during COVID-19 pandemic. The Depression, Anxiety and Stress Scale (DASS-21, Lovibond & Lovibond, 1995), The Pittsburgh Sleep Quality Index (PSQI, Buysse et al., 1989), The Rehearsal Scale (ECQ-R, Roger & Najarian, 1989), The Penn State Worry Questionnaire (PSWQ, Meyer et al., 1990), The Difficulties in Emotion Regulation Scale (DERS, Graz & Roemer, 2004) and The Composite Scale of Morningness (CSM, Smith et al., 1989) were used for the operationalization of the research constructs. All instruments demonstrated good metric characteristics. Data processing was carried out by setting up autoregressive cross-lagged panel models (CLPM) within structural equation modeling (SEM), separately for each of the assumed mediators (rumination, worry and emotional regulation) of the relationship between anxiety and sleep quality.
In this research, it was shown that anxiety precedes disturbed sleep quality, without the reciprocity of this relationship. In models with worry and rumination as mediators, a direct effect of anxiety on sleep quality was found, but not vice versa. Although both rumination and worry were shown to be predictors of sleep quality, which is expected based on the theory, they did not prove to be a mediator of the relationship between sleep quality and anxiety. In this study, anxiety does not precede rumination and worry, but the presence of these cognitive processes contributes to anxiety. In the model with emotional regulation as a mediator, full mediation was established - emotional regulation fully mediates the relationship between anxiety and sleep quality. The settings of the Cognitive Model of Insomnia are not applicable for explaining the relationship between anxiety and sleep quality in a non-clinical student population, but parts of The Hyperarousal Model of Insomnia and The Neuropathological Model related to emotional arousal completely explain the relationship between anxiety and sleep quality. It can be concluded that rumination and worry are cognitive factors important in the maintenance and appearance of anxiety symptoms, so they should be given attention in counseling work as potential transdiagnostic factors for various problems. Furthermore, in the case of disturbed sleep quality, which often appears with anxiety, it is necessary to work on adequate emotion regulation strategies, since they fully mediate the relationship between anxiety and sleep quality. The results offer a contribution to prevention science through guidelines for planning interventions and preventive activities, but also through epidemiological data, theory verification and guidelines for future research. |
