Klohnen & Bera (1998) conducted a longitudinal study over a period of 31 years. 142 women were involved, and they were interviewed in a time interval of 10 years about their attachments to their respective partners, and their general experiences with relationships.
The women were at the age of 21 divided into two groups depending on their attachment styles: (1) secure attachment; (2) insecure attachment.
The study found that those who were identified as having a secure attachment style, they also maintained their secure attachment at the age of 51. This might indicate that (1) attachment styles are established in the early years of living; (2) attachment styles rarely change over the years.
The study also found that women with a secure attachment had more happy, longer, and intimate relationships. Furthermore, these women reported more self-confidence and that they had had a happier childhood. As a result, they study concluded that women with a secure attachment were more happy in general.
Mikulincer (1998) examined the association between attachment styles and anger in both men and women through self-report measures. Both men and women with an insecure attachment style showed a higher degree of chronic anger or hostility toward others.
They also managed their anger attacks less appropriately. Those who had an anxious attachment style were not as hostile, but they experienced more often anger attacks and irritation. In contrary, those who had a secure attachment were less angry in general, and they had a better anger management, and verbal communication skills that prohibited anger attacks.
The results of this study might explain why securely attached women are more happy in general, and why they live in longer relationships than women with insecure attachment styles (Klohnen & Bera, 1998). Put simply, the ability to prohibit anger attacks may lead to better, and more stable relationships, and as a result, a happier life.